How does a Catholic understand Infallibility?

Taken from the 1917 Catholic Encyclopedia:

In general, exemption or immunity from liability to error or failure; in particular in theological usage, the supernatural prerogative by which the Church of Christ is, by a special Divine assistance, preserved from liability to error in her definitive dogmatic teaching regarding matters of faith and morals. In this article the subject will be treated under the following heads:

I. True Meaning of Infallibility
II. Proof of the Church's Infallibility
III. Organs of Infallibility
Ecumenical Councils
The Pope
Their Mutual Relations
IV. Scope and Object of Infallibility
V. What Teaching is Infallible?

True meaning of infallibility

It is well to begin by stating the ecclesiological truths that are assumed to be established before the question of infallibility arises. It is assumed:

that Christ founded His Church as a visible and perfect society;
that He intended it to be absolutely universal and imposed upon all men a solemn obligation actually to belong to it, unless inculpable ignorance should excuse them;
that He wished this Church to be one, with a visible corporate unity of faith, government, and worship; and that
in order to secure this threefold unity, He bestowed on the Apostles and their legitimate successors in the hierarchy — and on them exclusively — the plenitude of teaching, governing, and liturgical powers with which He wished this Church to be endowed.

And this being assumed, the question that concerns us is whether, and in what way, and to what extent, Christ has made His Church to be infallible in the exercise of her doctrinal authority.

It is only in connection with doctrinal authority as such that, practically speaking, this question of infallibility arises; that is to say, when we speak of the Church's infallibility we mean, at least primarily and principally, what is sometimes called active as distinguished from passive infallibility. We mean in other words that the Church is infallible in her objective definitive teaching regarding faith and morals, not that believers are infallible in their subjective interpretation of her teaching. This is obvious in the case of individuals, any one of whom may err in his understanding of the Church's teaching; nor is the general or even unanimous consent of the faithful in believing a distinct and independent organ of infallibility. Such consent indeed, when it can be verified as apart, is of the highest value as a proof of what has been, or may be, defined by the teaching authority, but, except in so far as it is thus the subjective counterpart and complement of objective authoritative teaching, it cannot be said to possess an absolutely decisive dogmatic value. It will be best therefore to confine our attention to active infallibility as such, as by so doing we shall avoid the confusion which is the sole basis of many of the objections that are most persistently and most plausibly urged against the doctrine of ecclesiastical infallibility.

Infallibility must be carefully distinguished both from Inspiration and from Revelation.

Inspiration signifies a special positive Divine influence and assistance by reason of which the human agent is not merely preserved from liability to error but is so guided and controlled that what he says or writes is truly the word of God, that God Himself is the principal author of the inspired utterance; but infallibility merely implies exemption from liability to error. God is not the author of a merely infallible, as He is of an inspired, utterance; the former remains a merely human document.

Revelation, on the other hand, means the making known by God, supernaturally of some truth hitherto unknown, or at least not vouched for by Divine authority; whereas infallibility is concerned with the interpretation and effective safeguarding of truths already revealed. Hence when we say, for example, that some doctrine defined by the pope or by an ecumenical council is infallible, we mean merely that its inerrancy is Divinely guaranteed according to the terms of Christ's promise to His Church, not that either the pope or the Fathers of the Council are inspired as were the writers of the Bible or that any new revelation is embodied in their teaching.

It is well further to explain:

that infallibility means more than exemption from actual error; it means exemption from the possibility of error;
that it does not require holiness of life, much less imply impeccability in its organs; sinful and wicked men may be God's agents in defining infallibly;
and finally that the validity of the Divine guarantee is independent of the fallible arguments upon which a definitive decision may be based, and of the possibly unworthy human motives that in cases of strife may appear to have influenced the result. It is the definitive result itself, and it alone, that is guaranteed to be infallible, not the preliminary stages by which it is reached.

If God bestowed the gift of prophecy on Caiphas who condemned Christ (John 11:49-52; 18:14), surely He may bestow the lesser gift of infallibility even on unworthy human agents. It is, therefore, a mere waste of time for opponents of infallibility to try to create a prejudice against the Catholic claim by pointing out the moral or intellectual shortcomings of popes or councils that have pronounced definitive doctrinal decisions, or to try to show historically that such decisions in certain cases were the seemingly natural and inevitable outcome of existing conditions, moral, intellectual, and political. All that history may be fairly claimed as witnessing to under either of these heads may freely be granted without the substance of the Catholic claim being affected.

Proof of the Church's infallibility

That the Church is infallible in her definitions on faith and morals is itself a Catholic dogma, which, although it was formulated ecumenically for the first time in the Vatican Council, had been explicitly taught long before and had been assumed from the very beginning without question down to the time of the Protestant Reformation. The teaching of the Vatican Council is to be found in Session III, cap. 4, where it is declared that "the doctrine of faith, which God has revealed, has not been proposed as a philosophical discovery to be improved upon by human talent, but has been committed as a Divine deposit to the spouse of Christ, to be faithfully guarded and infallibly interpreted by her"; and in Session IV, cap. 4, where it is defined that the Roman pontiff when he teaches ex cathedra "enjoys, by reason of the Divine assistance promised to him in blessed Peter, that infallibility with which the Divine Redeemer wished His Church to be endowed in defining doctrine regarding faith and morals". Even the Vatican Council, it will be seen, only introduces the general dogma of the Church's infallibility as distinct from that of the pope obliquely and indirectly, following in this respect the traditional usage according to which the dogma is assumed as an implicate of ecumenical magisterial authority. Instances of this will be given below and from these it will appear that, though the word infallibility as a technical term hardly occurs at all in the early councils or in the Fathers, the thing signified by it was understood and believed in and acted upon from the beginning. We shall confine our attention in this section to the general question, reserving the doctrine of papal infallibility for special treatment. This arrangement is adopted not because it is the best or most logical, but because it enables us to travel a certain distance in the friendly company of those who cling to the general doctrine of ecclesiastical infallibility while rejecting the papal claims. Taking the evidence both scriptural and traditional as it actually stands, one may fairly maintain that it proves papal infallibility in a simpler, more direct, and more cogent way than it proves the general doctrine independently; and there can be no doubt but that this is so if we accept as the alternative to papal infallibility the vague and unworkable theory of ecumenical infallibility which most High-Church Anglicans would substitute for Catholic teaching. Nor are the Eastern schismatical Churches much better off than the Anglican in this respect, except that each has retained a sort of virtual belief in its own infallibility, and that in practice they have been more faithful in guarding the doctrines infallibly defined by the early ecumenical councils. Yet certain Anglicans and all the Eastern Orthodox agree with Catholics in maintaining that Christ promised infallibility to the true Church, and we welcome their support as against the general Protestant denial of this truth.

Proof from Scripture
1

In order to prevent misconception and thereby to anticipate a common popular objection which is wholly based on a misconception it should be premised that when we appeal to the Scriptures for proof of the Church's infallible authority we appeal to them merely as reliable historical sources, and abstract altogether from their inspiration. Even considered as purely human documents they furnish us, we maintain, with a trustworthy report of Christ's sayings and promises; and, taking it to be a fact that Christ said what is attributed to Him in the Gospels, we further maintain that Christ's promises to the Apostles and their successors in the teaching office include the promise of such guidance and assistance as clearly implies infallibility. Having thus used the Scriptures as mere historical sources to prove that Christ endowed the Church with infallible teaching authority it is no vicious circle, but a perfectly legitimate logical procedure, to rely on the Church's authority for proof of what writings are inspired.

2

Merely remarking for the present that the texts in which Christ promised infallible guidance especially to Peter and his successors in the primacy might be appealed to here as possessing an a fortiori value, it will suffice to consider the classical texts usually employed in the general proof of the Church's infallibility; and of these the principal are:

Matthew 28:18-20;
Matthew 16:18;
John 14, 15, and 16;
I Timothy 3:14-15; and
Acts 15:28 sq.

Matthew 28:18-20

In Matthew 28:18-20, we have Christ's solemn commission to the Apostles delivered shortly before His Ascension: "All power is given to me in heaven and in earth. Going therefore, teach ye all nations; baptizing them in the name of the Father, and of the Son, and of the Holy Ghost; teaching them to observe all things whatsoever I have commanded you: and behold I am with you all days, even to the consummation of the world." In Mark 16:15-16, the same commission is given more briefly with the added promise of salvation to believers and the threat of damnation for unbelievers; "Go ye into the whole world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be condemned."

Now it cannot be denied by anyone who admits that Christ established a visible Church at all, and endowed it with any kind of effective teaching authority, that this commission, with all it implies, was given not only to the Apostles personally for their own lifetime, but to their successors to the end of time, "even to the consummation of the world". And assuming that it was the omniscient Son of God Who spoke these words, with a full and clear realization of the import which, in conjunction with His other promises, they were calculated to convey to the Apostles and to all simple and sincere believers to the end of time, the only reasonable interpretation to put upon them is that they contain the promise of infallible guidance in doctrinal teaching made to the Apostolic College in the first instance and then to the hierarchical college that was to succeed it.

In the first place it was not without reason that Christ prefaced His commission by appealing to the fullness of power He Himself had received: "All power is given to me", etc. This is evidently intended to emphasize the extraordinary character and extent of the authority He is communicating to His Church — an authority, it is implied, which He could not personally communicate were not He Himself omnipotent. Hence the promise that follows cannot reasonably be understood of ordinary natural providential guidance, but must refer to a very special supernatural assistance.

In the next place there is question particularly in this passage of doctrinal authority — of authority to teach the Gospel to all men — if Christ's promise to be with the Apostles and their successors to the end of time in carrying out this commission means that those whom they are to teach in His name and according to the plenitude of the power He has given them are bound to receive that teaching as if it were His own; in other words they are bound to accept it as infallible. Otherwise the perennial assistance promised would not really be efficacious for its purpose, and efficacious Divine assistance is what the expression used is clearly intended to signify. Supposing, as we do, that Christ actually delivered a definite body of revealed truth, to be taught to all men in all ages, and to be guarded from change or corruption by the living voice of His visible Church, it is idle to contend that this result could be accomplished effectively — in other words that His promise could be effectively fulfilled unless that living voice can speak infallibly to every generation on any question that may arise affecting the substance of Christ's teaching.

Without infallibility there could be no finality regarding any one of the great truths which have been identified historically with the very essence of Christianity; and it is only with those who believe in historical Christianity that the question need be discussed. Take, for instance, the mysteries of the Trinity and Incarnation. If the early Church was not infallible in her definitions regarding these truths, what compelling reason can be alleged today against the right to revive the Sabellian, or the Arian, or the Macedonian, or the Apollinarian, or the Nestorian, or the Eutychian controversies, and to defend some interpretation of these mysteries which the Church has condemned as heretical?

One may not appeal to the inspired authority of the Scriptures, since for the fact of their inspiration the authority of the Church must be invoked, and unless she be infallible in deciding this one would be free to question the inspiration of any of the New Testament writings. Nor, abstracting from the question of inspiration, can it be fairly maintained, in face of the facts of history, that the work of interpreting scriptural teaching regarding these mysteries and several other points of doctrine that have been identified with the substance of historical Christianity is so easy as to do away with the need of a living voice to which, as to the voice of Christ Himself, all are bound to submit.

Unity of Faith was intended by Christ to be one of the distinctive notes of His Church, and the doctrinal authority He set up was intended by His Divine guidance and assistance to be really effective in maintaining this unity; but the history of the early heresies and of the Protestant sects proves clearly, what might indeed have been anticipated a priori, that nothing less than an infallible public authority capable of acting decisively whenever the need should rise and pronouncing an absolutely final and irreformable judgment, is really efficient for this purpose. Practically speaking the only alternative to infallibility is private judgment, and this after some centuries of trial has been found to lead inevitably to utter rationalism. If the early definitions of the Church were fallible, and therefore reformable, perhaps those are right who say today that they ought to be discarded as being actually erroneous or even pernicious, or at least that they ought to be re-interpreted in a way that substantially changes their original meaning; perhaps, indeed, there is no such thing as absolute truth in matters religious! How, for example, is a Modernist who takes up this position to be met except by insisting that definitive teaching is irreversible and unchangeable; that it remains true in its original sense for all time; in other words that it is infallible? For no one can reasonably hold that fallible doctrinal teaching is irreformable or deny the right of later generations to question the correctness of earlier fallible definitions and call for their revision or correction, or even for their total abandonment.

From these considerations we are justified in concluding that if Christ really intended His promise to be with His Church to be taken seriously, and if He was truly the Son of God, omniscient and omnipotent, knowing history in advance and able to control its course, then the Church is entitled to claim infallible doctrinal authority. This conclusion is confirmed by considering the awful sanction by which the Church's authority is supported: all who refuse to assent to her teaching are threatened with eternal damnation. This proves the value Christ Himself set upon His own teaching and upon the teaching of the Church commissioned to teach in His name; religious indifferentism is here reprobated in unmistakable terms.

Nor does such a sanction lose its significance in this connection because the same penalty is threatened for disobedience to fallible disciplinary laws or even in some cases for refusing to assent to doctrinal teaching that is admittedly fallible. Indeed, every mortal sin, according to Christ's teaching, is punishable with eternal damnation. But if one believes in the objectivity of eternal and immutable truth, he will find it difficult to reconcile with a worthy conception of the Divine attributes a command under penalty of damnation to give unqualified and irrevocable internal assent to a large body of professedly Divine doctrine the whole of which is possibly false. Nor is this difficulty satisfactorily met, as some have attempted to meet it, by calling attention to the fact that in the Catholic system internal assent is sometimes demanded, under pain of grievous sin, to doctrinal decisions that do not profess to be infallible. For, in the first place, the assent to be given in such cases is recognized as being not irrevocable and irreversible, like the assent required in the case of definitive and infallible teaching, but merely provisional; and in the next place, internal assent is obligatory only on those who can give it consistently with the claims of objective truth on their conscience — this conscience, it is assumed, being directed by a spirit of generous loyalty to genuine Catholic principles.

To take a particular example, if Galileo who happened to be right while the ecclesiastical tribunal which condemned him was wrong, had really possessed convincing scientific evidence in favour of the heliocentric theory, he would have been justified in refusing his internal assent to the opposite theory, provided that in doing so he observed with thorough loyalty all the conditions involved in the duty of external obedience. Finally it should be observed that fallible provisional teaching, as such, derives its binding force principally from the fact that it emanates from an authority which is competent, if need be, to convert it into infallible definitive teaching. Without infallibility in the background it would be difficult to establish theoretically the obligation of yielding internal assent to the Church's provisional decisions.
Matthew 16:18

In Matthew 16:18, we have the promise that "the gates of hell shall not prevail" against the Church that is to be built on the rock; and this also, we maintain, implies the assurance of the Church's infallibility in the exercise of her teaching office. Such a promise, of course, must be understood with limitations according to the nature of the matter to which it is applied. As applied to sanctity, for example, which is essentially a personal and individual affair, it does not mean that every member of the Church or of her hierarchy is necessarily a saint, but merely that the Church, as whole, will be conspicuous among other things for the holiness of life of her members. As applied to doctrine, however — always assuming, as we do, that Christ delivered a body of doctrine the preservation of which in its literal truth was to be one of the chief duties of the Church — it would be a mockery to contend that such a promise is compatible with the supposition that the Church has possibly erred in perhaps the bulk of her dogmatic definitions, and that throughout the whole of her history she has been threatening men with eternal damnation in Christ's name for refusing to believe doctrines that are probably false and were never taught by Christ Himself. Could this be the case, would it not be clear that the gates of hell can prevail and probably have prevailed most signally against the Church?
John 14-16

In Christ's discourse to the Apostles at the Last Supper several passages occur which clearly imply the promise of infallibility: "I will ask the Father, and he shall give you another Paraclete, that he may abide with you forever. The spirit of truth . . . he shall abide with you, and shall be in you" (John 14:16, 17). "But the Paraclete, the Holy Ghost, whom the Father will send in my name, he will teach you all things, and bring all things to your mind, whatsoever I shall have said to you" (ibid. 26). "But when he, the spirit of truth, is come, he will teach you all truth (John 16:13). And the same promise is renewed immediately before the Ascension (Acts 1:8). Now what does the promise of this perennial and efficacious presence and assistance of the Holy Ghost, the Spirit of truth, mean in connection with doctrinal authority, except that the Third Person of the Blessed Trinity is made responsible for what the Apostles and their successors may define to be part of Christ's teaching? But insofar as the Holy Ghost is responsible for Church teaching, that teaching is necessarily infallible: what the Spirit of truth guarantees cannot be false.
1 Timothy 3:15

In 1 Timothy 3:15, St. Paul speaks of "the house of God, which is the church of the living God, the pillar and ground of the truth"; and this description would be something worse than mere exaggeration if it had been intended to apply to a fallible Church; it would be a false and misleading description. That St. Paul, however, meant it to be taken for sober and literal truth is abundantly proved by what he insists upon so strongly elsewhere, namely, the strictly Divine authority of the Gospel which he and the other Apostles preached, and which it was the mission of their successors to go on preaching without change or corruption to the end of time. "When you had received of us", he writes to the Thessalonians, "the word of the hearing of God, you received it not as the word of men, but (as it is indeed) the word of God, who worketh in you that have believed" (1 Thessalonians 2:13). The Gospel, he tells the Corinthians, is intended to bring "into captivity every understanding unto the obedience of Christ" (2 Corinthians 10:5). Indeed, so fixed and irreformable is the doctrine that has been taught that the Galatians (1:8) are warned to anathematize any one, even an angel from heaven, who should preach to them a Gospel other than that which St. Paul had preached. Nor was this attitude — which is intelligible only on the supposition that the Apostolic College was infallible — peculiar to St. Paul. The other Apostles and apostolic writers were equally strong in anathematizing those who preached another Christianity than that which the Apostles had preached (cf. 2 Peter 2:1 sqq.; 1 John 4:1 sqq.; 2 John 7 sqq.; Jude 4); and St. Paul makes it clear that it was not to any personal or private views of his own that he claimed to make every understanding captive, but to the Gospel which Christ had delivered to the Apostolic body. When his own authority as an Apostle was challenged, his defense was that he had seen the risen Saviour and received his mission directly from Him, and that his Gospel was in complete agreement with that of the other Apostles (see, v.g., Galatians 2:2-9).
Acts 15:28

Finally, the consciousness of corporate infallibility is clearly signified in the expression used by the assembled Apostles in the decree of the Council of Jerusalem: "It hath seemed good to the Holy Ghost and to us, to lay no further burden upon you", etc. (Acts 15:28). It is true that the specific points here dealt with are chiefly disciplinary rather than dogmatic, and that no claim to infallibility is made in regard to purely disciplinary questions as such; but behind, and independent of, disciplinary details there was the broad and most important dogmatic question to be decided, whether Christians, according to Christ's teaching, were bound to observe the Old Law in its integrity, as orthodox Jews of the time observed it. This was the main issue at stake, and in deciding it the Apostles claimed to speak in the name and with the authority of the Holy Ghost. Would men who did not believe that Christ's promises assured them of an infallible Divine guidance have presumed to speak in this way? And could they, in so believing, have misunderstood the Master's meaning?

Proof from Tradition

If, during the early centuries, there was no explicit and formal discussion regarding ecclesiastical infallibility as such, yet the Church, in her corporate capacity, after the example of the Apostles at Jerusalem, always acted on the assumption that she was infallible in doctrinal matters and all the great orthodox teachers believed that she was so. Those who presumed, on whatever grounds, to contradict the Church's teaching were treated as representatives of Antichrist (cf. 1 John 2:18 sq.), and were excommunicated and anathematized.

It is clear from the letters of St. Ignatius of Antioch how intolerant he was of error, and how firmly convinced that the episcopal body was the Divinely ordained and Divinely guided organ of truth; nor can any student of early Christian literature deny that, where Divine guidance is claimed in doctrinal matters, infallibility is implied.
So intolerant of error was St. Polycarp that, as the story goes, when he met Marcion on the street in Rome, he did not hesitate to denounce the heretic to his face as "the firstborn of Satan". This incident, whether it be true or not, is at any rate thoroughly in keeping with the spirit of the age and such a spirit is incompatible with belief in a fallible Church.
St. Irenaeus, who in the disciplinary Paschal question favoured compromise for the sake of peace, took an altogether different attitude in the doctrinal controversy with the Gnostics; and the great principle on which he mainly relies in refuting the heretics is the principle of a living ecclesiastical authority for which he virtually claims infallibility. For example he says: "Where the Church is, there also is the Spirit of God, and where the Spirit of God is there is the Church, and every grace: for the Spirit is truth" (Adv. Haer. III, xxiv, 1); and again, Where the charismata of the Lord are given, there must we seek the truth, i.e. with those to whom belongs the ecclesiastical succession from the Apostles, and the unadulterated and incorruptible word. It is they who . . . are the guardians of our faith . . . and securely [sine periculo] expound the Scriptures to us" (op. cit., IV xxvi, 5).
Tertullian, writing from the Catholic standpoint, ridicules the suggestion that the universal teaching of the Church can be wrong: "Suppose now that all [the Churches] have erred . . . [This would mean that] the Holy Spirit has not watched over any of them so as to guide it into the truth, although He was sent by Christ, and asked from the Father for this very purpose — that He might be the teacher of truth" (doctor veritatis — "De Praescript", xxxvi, in P.L., II, 49).

St. Cyprian compares the Church to an incorruptible virgin: Adulterari non potest sponsa Christi, incorrupta est et pudica (De unitate eccl.).

It is needless to go on multiplying citations, since the broad fact is indisputable that in the ante-Nicene, no less than in the post-Nicene, period all orthodox Christians attributed to the corporate voice of the Church, speaking through the body of bishops in union with their head and centre, all the fullness of doctrinal authority which the Apostles themselves had possessed; and to question the infallibility of that authority would have been considered equivalent to questioning God's veracity and fidelity. It was for this reason that during the first three centuries the concurrent action of the bishops dispersed throughout the world proved to be effective in securing the condemnation and exclusion of certain heresies and maintaining Gospel truth in its purity; and when from the fourth century onwards it was found expedient to assemble ecumenical councils, after the example of the Apostles at Jerusalem, it was for the same reason that the doctrinal decision of these councils were held to be absolutely final and irreformable. Even the heretics, for the most part recognized this principle in theory; and if in fact they often refused to submit, they did so as a rule on the ground that this or that council was not really ecumenical, that it did not truly express the corporate voice of the Church, and was not, therefore, infallible. This will not be denied by anyone who is familiar with the history of the doctrinal controversies of the fourth and fifth centuries, and within the limits of this article we cannot do more than call attention to the broad conclusion in proof of which it would be easy to cite a great number of particular facts and testimonies.

Objections alleged

Several of the objections usually urged against ecclesiastical infallibility have been anticipated in the preceding sections; but some others deserve a passing notice here.

1

It has been urged that neither a fallible individual nor a collection of fallible individuals can constitute an infallible organ. This is quite true in reference to natural knowledge and would be also true as applied to Church authority if Christianity were assumed to be a mere product of natural reason. But we set out from an entirely different standpoint. We assume as antecedently and independently established that God can supernaturally guide and enlighten men, individually or collectively, in such a way that, notwithstanding the natural fallibility of human intelligence, they may speak and may be known with certainty to speak in His name and with His authority, so that their utterance may be not merely infallible but inspired. And it is only with those who accept this standpoint that the question of the Church's infallibility can be profitably discussed.

2

Again, it is said that even those who accept the supernatural viewpoint must ultimately fall back on fallible human reasoning in attempting to prove infallibility; that behind any conclusion that is proposed on so-called infallible authority there always lurks a premise which cannot claim for itself more than a merely human and fallible certainty; and that, since the strength of a conclusion is no greater than that of its weaker premise, the principle of infallibility is a useless as well as an illogical importation into Christian theology. In reply it is to be observed that this argument, if valid, would prove very much more than it is here introduced to prove; that it would indeed undermine the very foundations of Christian faith. For example, on purely rational grounds I have only moral certainty that God Himself is infallible or that Christ was the infallible mediator of a Divine Revelation; yet if I am to give a rational defense of my faith, even in mysteries which I do not comprehend, I must do so by appealing to the infallibility of God and of Christ. But according to the logic of the objection this appeal would be futile and the assent of faith considered as a rational act would be no firmer or more secure than natural human knowledge. The truth is that the inferential process here and in the case of ecclesiastical infallibility transcends the rule of formal logic that is alleged. Assent is given not to the logical force of the syllogism, but directly to the authority which the inference serves to introduce; and this holds good in a measure even when there is question of mere fallible authority. Once we come to believe in and rely upon authority we can afford to overlook the means by which we were brought to accept it, just as a man who has reached a solid standing place where he wishes to remain no longer relies on the frail ladder by which he mounted. It cannot be said that there is any essential difference in this respect between Divine and ecclesiastical infallibility. The latter of course is only a means by which we are put under subjection to the former in regard to a body of truth once revealed and to be believed by all men to the end of time, and no one can fairly deny that it is useful, not to say necessary, for that purpose. Its alternative is private judgment, and history has shown to what results this alternative inevitably leads.

3

Again, it is urged that the kind of submission demanded by infallible authority is incompatible with the rights of reason and of legitimate inquiry and speculation, and tends to give to one's faith in his Creed a dry, formal, proud, and intolerant character which contrasts unfavourably with the warmhearted, humble, and tolerant faith of the man who believes on conviction after free personal inquiry. In reply it is sufficient to say that submission to infallible authority implies no abdication of reason, nor does it impose any undue check on the believer's freedom to pursue inquiry and speculation. Were it so, how could one believe in revealed doctrine at all without being accused, as unbelievers do accuse Christians, of committing intellectual suicide? If one believes in revelation at all one does so in deference to God's authority an authority that is surely infallible; and so far as the principle of the objection is concerned there is no difference between ecclesiastical and Divine infallibility. It is somewhat surprising, therefore, that professing Christians should recur to such an argument, which, if consistently urged, would be fatal to their own position. And as regards freedom of inquiry and speculation in reference to revealed doctrines themselves, it should be observed that true freedom in this as in other matters does not mean unbridled licence. Really effective authoritative control is always necessary to prevent liberty from degenerating into anarchy, and in the sphere of Christian doctrine — we are arguing only with those who admit that Christ delivered a body of doctrine that was to be held as eternally true — from the very nature of the case, the only effective barrier against Rationalism — the equivalent of political anarchy — is an infallible ecclesiastical authority. This authority therefore, by its decisions merely curtails personal freedom of inquiry in religious matters in the same way, and by an equally valid title, as the supreme authority in the State, restricts the liberty of private citizens.

Moreover, as in a well ordered state there remains within the law a large margin for the exercise of personal freedom, so in the Church there is a very extensive domain which is given over to theological speculation; and even in regard to doctrines that have been infallibly defined there is always room for further inquiry so as the better to understand, explain, defend, and expand them. The only thing one may not do is to deny or change them. Then, in reply to the charge of intolerance, it may be said that if this be taken to mean an honest and sincere repudiation of Liberalism and Rationalism, infallibilists must plead guilty to the charge; but in doing so they are in good company. Christ Himself was intolerant in this sense; so were His Apostles; and so were all the great champions of historical Christianity in every age. Finally it is altogether untrue, as every Catholic knows and feels, that faith which allows itself to be guided by infallible ecclesiastical authority is less intimately personal or less genuine in any way than faith based on private judgment. If this docile loyalty to Divine authority which true faith implies means anything, it means that one must listen to the voice of those whom God has expressly appointed to teach in His name, rather than to one's own private judgment deciding what God's teaching ought to be. For to this, in final analysis, the issue is reduced; and he who chooses to make himself, instead of the authority which God has instituted, the final arbiter in matters of faith is far from possessing the true spirit of faith, which is the foundation of charity and of the whole supernatural life.

4

Again it is urged by our opponents that infallibility as exercised by the Catholic Church has shown itself to be a failure, since, in the first place, it has not prevented schisms and heresies in the Christian body, and, in the second place, has not attempted to settle for Catholics themselves many important questions, the final settlement of which would be a great relief to believers by freeing them from anxious and distressing doubts. In reply to the first point it is enough to say that the purpose for which Christ endowed the Church with infallibility was not to prevent the occurrence of schisms and heresies, which He foresaw and foretold, but to take away all justification for their occurrence; men were left free to disrupt the unity of Faith inculcated by Christ in the same way as they were left free to disobey any other commandment, but heresy was intended to be no more justifiable objectively than homicide or adultery. To reply to the second point we would observe that it seems highly inconsistent for the same objector to blame Catholics in one breath for having too much defined doctrine in their Creed and, in the next breath, to find fault with them for having too little. Either part of the accusation, in so far as it is founded, is a sufficient answer to the other. Catholics as a matter of fact do not feel in any way distressed either by the restrictions, on the one hand, which infallible definitions impose or, on the other hand, by the liberty as to non-defined matters which they enjoy, and they can afford to decline the services of an opponent who is determined at all costs to invent a grievance for them. The objection is based on a mechanical conception of the function of infallible authority, as if this were fairly comparable, for example, to a clock which is supposed to tell us unerringly not only the large divisions of time such as the hours, but also, if it is to be useful as a timekeeper, the minutes and even the seconds. Even if we admit the propriety of the illustration, it is obvious that a clock which records the hours correctly, without indicating the smaller fractions of time, is a very useful instrument, and that it would be foolish to refuse to follow it because it is not provided with a minute or a second hand on the dial. But it is perhaps best to avoid such mechanical illustrations altogether. The Catholic believer who has real faith in the efficiency of Christ's promises will not doubt but that the Holy Ghost Who abides in the Church, and Whose assistance guarantees the infallibility of her definitions, will also provide that any definition that may be necessary or expedient for the safeguarding of Christ's teaching will be given at the opportune moment, and that such definable questions as are left undefined may, for the time being at least, be allowed to remain so without detriment to the faith or morals of the faithful.

5

Finally, it is objected that the acceptance of ecclesiastical infallibility is incompatible with the theory of doctrinal development which Catholics commonly admit. But so far is this from being true that it is impossible to frame any theory of development, consistent with Catholic principles, in which authority is not recognized as a guiding and controlling factor. For development in the Catholic sense does not mean that the Church ever changes her definitive teaching, but merely that as time goes on and human science advances, her teaching is more deeply analyzed, more fully comprehended, and more perfectly coordinated and explained in itself and in its bearings on other departments of knowledge. It is only on the false supposition that development means change in definitive teaching that the objection has any real force. We have confined our attention to what we may describe as the rational objections against the Catholic doctrine of infallibility, omitting all mention of the interminable exegetical difficulties which Protestant theologians have raised against the Catholic interpretation of Christ's promises to His Church. The necessity for noticing these latter has been done away with by the growth of Rationalism, the logical successor of old-time Protestantism. If the infallible Divine authority of Christ, and the historicity of His promises to which we have appealed be admitted, there is no reasonable escape from the conclusion which the Catholic Church has drawn from those promises.
Organs of infallibility

Having established the general doctrine of the Church's infallibility, we naturally proceed to ask what are the organs through which the voice of infallible authority makes itself heard. We have already seen that it is only in the episcopal body which has succeeded to the college of Apostles that infallible authority resides, and that it is possible for the authority to be effectively exercised by this body, dispersed throughout the world, but united in bonds of communion with Peter's successor, who is its visible head and centre. During the interval from the council of the Apostles at Jerusalem to that of their successors at Nicaea this ordinary everyday exercise of episcopal authority was found to be sufficiently effective for the needs of the time, but when a crisis like the Arian heresy arose, its effectiveness was discovered to be inadequate, as was indeed inevitable by reason of the practical difficulty of verifying that fact of moral unanimity, once any considerable volume of dissent had to be faced. And while for subsequent ages down to our own day it continues to be theoretically true that the Church may, by the exercise of this ordinary teaching authority arrive at a final and infallible decision regarding doctrinal questions, it is true at the same time that in practice it may be impossible to prove conclusively that such unanimity as may exist has a strictly definitive value in any particular case, unless it has been embodied in a decree of an ecumenical council, or in the ex cathedra teaching of the pope, or, at least, in some definite formula such as the Athanasian Creed. Hence, for practical purposes and in so far as the special question of infallibility is concerned, we may neglect the so called magisterium ordinarium ("ordinary magisterium") and confine our attention to ecumenical councils and the pope.

Ecumenical councils
1

An ecumenical or general, as distinguished from a particular or provincial council, is an assembly of bishops which juridically represents the universal Church as hierarchically constituted by Christ; and, since the primacy of Peter and of his successor, the pope, is an essential feature in the hierarchical constitution of the Church, it follows that there can be no such thing as an ecumenical council independent of, or in opposition to, the pope. No body can perform a strictly corporate function validly without the consent and co-operation of its head. Hence:

the right to summon an ecumenical council belongs properly to the pope alone, though by his express or presumed consent given ante or post factum, the summons may be issued, as in the case of most of the early councils, in the name of the civil authority. For ecumenicity in the adequate sense all the bishops of the world in communion with the Holy See should be summoned, but it is not required that all or even a majority should be present.
As regards the conduct of the deliberations, the right of presidency, of course, belongs to the pope or his representative; while as regards the decisions arrived at unanimity is not required.
Finally, papal approbation is required to give ecumenical value and authority to conciliar decrees, and this must be subsequent to conciliar action, unless the pope, by his personal presence and conscience, has already given his official ratification (for details see GENERAL COUNCILS).

2

That an ecumenical council which satisfies the conditions above stated is an organ of infallibility will not be denied by anyone who admits that the Church is endowed with infallible doctrinal authority. How, if not through such an organ, could infallible authority effectively express itself, unless indeed through the pope? If Christ promised to be present with even two or three of His disciples gathered together in His name (Matthew 18:20), a fortiori He will be present efficaciously in a representative assembly of His authorized teachers; and the Paraclete whom He promised will be present, so that whatever the council defines may be prefaced with the Apostolic formula, "it has seemed good to the Holy Ghost and to us." And this is the view which the councils held regarding their own authority and upon which the defender of orthodoxy insisted. The councils insisted on their definitions being accepted under pain of anathema, while St. Athanasius, for example, says that "the word of the Lord pronounced by the ecumenical synod of Nicaea stands for ever" (Ep. ad Afros, n. 2) and St. Leo the Great proves the unchangeable character of definitive conciliar teaching on the ground that God has irrevocably confirmed its truth "universae fraternitatis irretractabili firmavit assensu" (Ep. 120, 1).

3

It remains to be observed, in opposition to the theory of conciliar infallibility usually defended by High Church Anglicans that once the requisite papal confirmation has been given the doctrinal decisions of an ecumenical council become infallible and irreformable; there is no need to wait perhaps hundreds of years for the unanimous acceptance and approbation of the whole Christian world. Such a theory really amounts to a denial of conciliar infallibility, and sets up in the final court of appeal an altogether vague and ineffective tribunal. If the theory be true, were not the Arians perfectly justified in their prolonged struggle to reverse Nicaea, and has not the persistent refusal of the Nestorians down to our own day to accept Ephesus and of the Monophysites to accept Chalcedon been sufficient to defeat the ratification of those councils? No workable rule can be given for deciding when such subsequent ratification as this theory requires becomes effective and even if this could be done in the case of some of the earlier councils whose definitions are received by the Anglicans, it would still be true that since the Photian schism it has been practically impossible to secure any such consensus as is required — in other words that the working of infallible authority, the purpose of which is to teach every generation, has been suspended since the ninth century, and that Christ's promises to His Church have been falsified. It is consoling, no doubt, to cling to the abstract doctrine of an infallible authority but if one adopts a theory which represents that authority as unable to fulfil its appointed task during the greater part of the Church's life, it is not easy to see how this consolatory belief is anything more than a delusion.

Explanation of papal infallibility

The Vatican Council has defined as "a divinely revealed dogma" that "the Roman Pontiff, when he speaks ex cathedra — that is, when in the exercise of his office as pastor and teacher of all Christians he defines, by virtue of his supreme Apostolic authority, a doctrine of faith or morals to be held by the whole Church — is, by reason of the Divine assistance promised to him in blessed Peter, possessed of that infallibility with which the Divine Redeemer wished His Church to be endowed in defining doctrines of faith and morals; and consequently that such definitions of the Roman Pontiff are irreformable of their own nature (ex sese) and not by reason of the Church's consent" (Denzinger no. 1839 — old no. 1680). For the correct understanding of this definition it is to be noted that:

what is claimed for the pope is infallibility merely, not impeccability or inspiration (see above under I).
the infallibility claimed for the pope is the same in its nature, scope, and extent as that which the Church as a whole possesses; his ex cathedra teaching does not have to be ratified by the Church's in order to be infallible.
infallibility is not attributed to every doctrinal act of the pope, but only to his ex cathedra teaching; and the conditions required for ex cathedra teaching are mentioned in the Vatican decree:
The pontiff must teach in his public and official capacity as pastor and doctor of all Christians, not merely in his private capacity as a theologian, preacher or allocutionist, nor in his capacity as a temporal prince or as a mere ordinary of the Diocese of Rome. It must be clear that he speaks as spiritual head of the Church universal.

Then it is only when, in this capacity, he teaches some doctrine of faith or morals that he is infallible (see below, IV).
Further it must be sufficiently evident that he intends to teach with all the fullness and finality of his supreme Apostolic authority, in other words that he wishes to determine some point of doctrine in an absolutely final and irrevocable way, or to define it in the technical sense (see DEFINITION). These are well-recognized formulas by means of which the defining intention may be manifested.

Finally for an ex cathedra decision it must be clear that the pope intends to bind the whole Church. To demand internal assent from all the faithful to his teaching under pain of incurring spiritual shipwreck (naufragium fidei) according to the expression used by Pius IX in defining the Immaculate Conception of the Blessed Virgin. Theoretically, this intention might be made sufficiently clear in a papal decision which is addressed only to a particular Church; but in present day conditions, when it is so easy to communicate with the most distant parts of the earth and to secure a literally universal promulgation of papal acts, the presumption is that unless the pope formally addresses the whole Church in the recognized official way, he does not intend his doctrinal teaching to be held by all the faithful as ex cathedra and infallible.

It should be observed in conclusion that papal infallibility is a personal and incommunicable charisma, which is not shared by any pontifical tribunal. It was promised directly to Peter, and to each of Peter's successors in the primacy, but not as a prerogative the exercise of which could be delegated to others. Hence doctrinal decisions or instructions issued by the Roman congregations, even when approved by the pope in the ordinary way, have no claim to be considered infallible. To be infallible they must be issued by the pope himself in his own name according to the conditions already mentioned as requisite for ex cathedra teaching.

Proof of papal infallibility from Holy Scripture

From Holy Scripture, as already stated, the special proof of the pope's infallibility is, if anything, stronger and clearer than the general proof of the infallibility of the Church as a whole, just as the proof of his primacy is stronger and clearer than any proof that can be advanced independently for the Apostolic authority of the episcopate.

Matthew 16:18

"Thou art Peter (Kepha)", said Christ, "and upon this rock (kepha) I will build my church, and the gates of hell shall not prevail against it" (Matthew 16:18). Various attempts have been made by opponents of the papal claims to get rid of the only obvious and natural meaning of these words, according to which Peter is to be the rock-foundation of the Church, and the source of its indefectibility against the gates of hell. It has been suggested, for example, that "this rock" is Christ Himself or that it is Peter's faith (typifying the faith of future believers), not his person and office, on which the Church is to be built. But these and similar interpretations simply destroy the logical coherency of Christ's statement and are excluded by the Greek and Latin texts, in which a kind of play upon the words Petros (Petrus) and petra is clearly intended, and still more forcibly by the original Aramaic which Christ spoke, and in which the same word Kêpha must have been used in both clauses. And granting, as the best modern non-Catholic commentators grant, that this text of St. Matthew contains the promise that St. Peter was to be the rock-foundation of the Church, it is impossible to deny that Peter's successors in the primacy are heirs to this promise — unless, indeed, one is willing to admit the principle, which would be altogether subversive of the hierarchial system, that the authority bestowed by Christ on the Apostles was not intended to be transmitted to their successors, and to abide in the Church permanently. Peter's headship was as much emphasized by Christ Himself, and was as clearly recognized in the infant Church, as was the enduring authority of the episcopal body; and it is a puzzle which the Catholic finds it hard to solve, how those who deny that the supreme authority of Peter's successor is an essential factor in the constitution of the Church can consistently maintain the Divine authority of the episcopate. Now, as we have already seen, doctrinal indefectibility is certainly implied in Christ's promise that the gates of hell shall not prevail against His Church, and cannot be effectively secured without doctrinal infallibility; so that if Christ's promise means anything — if Peter's successor is in any true sense the foundation and source of the Church's indefectibility — he must by virtue of this office be also an organ of ecclesiastical infallibility. The metaphor used clearly implies that it was the rock-foundation which was to give stability to the superstructure, not the superstructure to the rock.

Nor can it be said that this argument fails by proving too much — by proving, that is, that the pope should be impeccable, or at least that he should be a saint, since, if the Church must be holy in order to overcome the gates of hell, the example and inspiration of holiness ought to be given by him who is the visible foundation of the Church's indefectibility. From the very nature of the case a distinction must be made between sanctity or impeccability, and infallible doctrinal authority. Personal sanctity is essentially incommunicable as between men, and cannot affect others except in fallible and indirect ways, as by prayer or example; but doctrinal teaching which is accepted as infallible is capable of securing that certainty and consequent unity of Faith by which, as well as by other bonds, the members of Christ's visible Church were to be "compacted and fitly joined together" (Ephesians 4:16). It is true, of course, that infallible teaching, especially on moral questions, helps to promote sanctity among those who accept, but no one will seriously suggest that, if Christ had made the pope impeccable as well as infallible, He would thereby have provided for the personal sanctity of individual believers any more efficiently than, on Catholic principles, He has actually done.

Luke 22:31-32

Here Christ says to St. Peter and to his successors in the primacy: "Simon, Simon, behold Satan hath desired to have you, that he may sift you as wheat: But I have prayed for thee, that thy faith fail not: and thou, being once converted, confirm thy brethren." This special prayer of Christ was for Peter alone in his capacity as head of the Church, as is clear from the text and context; and since we cannot doubt the efficacy of Christ's prayer, it followed that to St. Peter and his successors the office was personally committed of authoritatively confirming the brethren — other bishops, and believers generally — in the faith; and this implies infallibility.
John 21:15-17

Here we have the record of Christ's thrice-repeated demand for a confession of Peter's love and the thrice-repeated commission to feed the lambs and the sheep:

When therefore they had dined, Jesus said to Simon (Peter): Simon, son of John, do you love me more than these? He said to him: Yes, Lord, you know that I love you. He said to him: Feed my lambs. He said to him again: Simon, son of John, do you love me? He said to him: Yes, Lord, you know that I love you. He said to him: Feed my lambs. He said to him the third time: Simon, son of John, do you love me? Peter was grieved, because he had said to him the third time: Do you love me? And he said to him: Lord, you know all things: you know that I love you. He said to him: Feed my sheep.

Here the complete and supreme pastoral charge of the whole of Christ's flock — sheep as well as lambs — is given to St. Peter and his successors, and in this is undoubtedly comprised supreme doctrinal authority. But, as we have already seen, doctrinal authority in the Church cannot be really effective in securing the unity of faith intended by Christ, unless in the last resort it is infallible. It is futile to contend, as non Catholics have often done, that this passage is merely a record of Peter's restoration to his personal share in the collective Apostolic authority, which he had forfeited by his triple denial. It is quite probable that the reason why Christ demanded the triple confession of love was as a set-off to the triple denial; but if Christ's words in this and in the other passages quoted mean anything, and if they are to be understood in the same obvious and natural way in which defenders of the Divine authority of the episcopate understand the words elsewhere addressed to the Apostles collectively, there is no denying that the Petrine and papal claims are more clearly supported by the Gospels than are those of a monarchical episcopate. It is equally futile to contend that these promises were made, and this power given, to Peter merely as the representative of the Apostolic college: in the texts of the Gospel, Peter is individually singled out and addressed with particular emphasis, so that, unless by denying with the rationalist the genuineness of Christ's words, there is no logical escape from the Catholic position. Furthermore, it is clear from such evidence as the Acts of the Apostles supply, that Peter's supremacy was recognized in the infant Church (see PRIMACY) and if this supremacy was intended to be efficacious for the purpose for which it was instituted, it must have included the prerogative of doctrinal infallibility.

Proof of papal infallibility from Tradition

One need not expect to find in the early centuries a formal and explicit recognition throughout the Church either of the primacy or of the infallibility of the pope in the terms in which these doctrines are defined by the Vatican Council. But the fact cannot be denied that from the beginning there was a widespread acknowledgment by other churches of some kind of supreme authority in the Roman pontiff in regard not only to disciplinary but also to doctrinal affairs. This is clear for example, from:

Clement's Letter to the Corinthians at the end of the first century,
the way in which, shortly afterwards, Ignatius of Antioch addresses the Roman Church;
the conduct of Pope Victor in the latter half of the second century, in connection with the paschal controversy;
the teaching of St. Irenaeus, who lays it down as a practical rule that conformity with Rome is a sufficient proof of Apostolicity of doctrine against the heretics (Adv. Haer., III, iii);
the correspondence between Pope Dionysius and his namesake at Alexandria in the second half of the third century;
and from many other facts that might be mentioned (see PRIMACY).

Even heretics recognized something special in the doctrinal authority of the pope, and some of them, like Marcion in the second century and Pelagius and Caelestius in the first quarter of the fifth, appealed to Rome in the hope of obtaining a reversal of their condemnation by provincial bishops or synods. And in the age of the councils, from Nicaea onwards, there is a sufficiently explicit and formal acknowledgment of the doctrinal supremacy of the Bishop of Rome.

St. Augustine, for example, voices the prevailing Catholic sentiment when in reference to the Pelagian affair he declares, in a sermon delivered at Carthage after the receipt of Pope Innocent's letter, confirming the decrees of the Council of Carthage: "Rome's reply has come: the case is closed" (Inde etiam rescripta venerunt: causa finita est. Serm. 131, c.x);
and again when in reference to the same subject he insists that "all doubt bas been removed by the letter of Pope Innocent of blessed memory" (C. Duas Epp. Pelag., II, iii, 5).

And what is still more important, is the explicit recognition in formal terms, by councils which are admitted to be ecumenical, of the finality, and by implication the infallibility of papal teaching.

Thus the Fathers of Ephesus (431) declare that they "are compelled" to condemn the heresy of Nestorius "by the sacred canons and by the letter of our holy father and co-minister, Celestine the Bishop of Rome."
Twenty years later (451) the Fathers of Chalcedon, after hearing Leo's letter read, make themselves responsible for the statement: "so do we all believe . . . Peter has spoken through Leo."
More than two centuries later, at the Third Council of Constantinople (680-681), the same formula is repeated: "Peter has spoken through Agatho."
After the lapse of still two other centuries, and shortly before the Photian schism, the profession of faith drawn up by Pope Hormisdas was accepted by the Fourth Council of Constantinople (869-870), and in this profession, it is stated that, by virtue of Christ's promise: "Thou art Peter, etc."; "the Catholic religion is preserved inviolable in the Apostolic See."
Finally the reunion Council of Florence (1438-1445), repeating what had been substantially contained in the profession of faith of Michael Palaeologus approved by the Second Council of Lyons (1274), defined "that the holy Apostolic see and the Roman pontiff holds the primacy over the whole world; and that the Roman pontiff himself is the successor of the blessed Peter Prince of the Apostles and the true Vicar of Christ, and the head of the whole Church, and the father and teacher of all Christians, and that to him in blessed Peter the full power of feeding, ruling and governing the universal Church was given by our Lord Jesus Christ, and this is also recognized in the acts of the ecumenical council and in the sacred canons (quemadmodum etiam . . . continetur.

Thus it is clear that the Vatican Council introduced no new doctrine when it defined the infallibility of the pope, but merely re-asserted what had been implicitly admitted and acted upon from the beginning and had even been explicitly proclaimed and in equivalent terms by more than one of the early ecumenical councils. Until the Photian Schism in the East and the Gallican movement in the West there was no formal denial of papal supremacy, or of papal infallibility as an adjunct of supreme doctrinal authority, while the instances of their formal acknowledgment that have been referred to in the early centuries are but a few out of the multitude that might be quoted.

Objections alleged

The only noteworthy objections against papal infallibility, as distinct from the infallibility of the Church at large, are based on certain historical instances in which it is alleged that certain popes in the ex cathedra exercise of their office have actually taught heresy and condemned as heretical what has afterwards turned out to be true. The chief instances usually appealed to are those of Popes Liberius, Honorius, and Vigilius in the early centuries, and the Galileo affair at the beginning of the seventeenth century.

Pope Liberius

Liberius, it is alleged, subscribed an Arian or Semi-Arian creed drawn up by the Council of Sirmium and anathematized St. Athanasius, the great champion of Nicaea, as a heretic. But even if this were an accurate statement of historical fact, it is a very inadequate statement. The all-important circumstance should be added that the pope so acted under pressure of a very cruel coercion, which at once deprives his action of any claim to be considered ex cathedra, and that he himself, as soon as he had recovered his liberty, made amends for the moral weakness he had been guilty of. This is a quite satisfactory answer to the objection, but it ought to be added that there is no evidence whatever that Liberius ever anathematized St. Athanasius expressly as a heretic, and that it remains a moot point which of three or four Sirmian creeds he subscribed, two of which contained no positive assertion of heretical doctrine and were defective merely for the negative reason that they failed to insist on the full definition of Nicaea.

Pope Honorius

The charge against Pope Honorius is a double one: that, when appealed to in the Monothelite controversy, he actually taught the Monothelite heresy in his two letters to Sergius; and that he was condemned as a heretic by the Sixth Ecumenical Council, the decrees of which were approved by Leo II. But in the first place it is quite clear from the tone and terms of these letters that, so far from intending to give any final, or ex cathedra, decision on the doctrinal question at issue, Honorius merely tried to allay the rising bitterness of the controversy by securing silence. In the next place, taking the letters as they stand, the very most that can be clearly and incontrovertibly deduced from them is, that Honorius was not a profound or acute theologian, and that he allowed himself to be confused and misled by the wily Sergius as to what the issue really was and too readily accepted the latter's misrepresentation of his opponents' position, to the effect that the assertion of two wills in Christ meant two contrary or discordant wills. Finally, in reference to the condemnation of Honorius as a heretic, it is to be remembered that there is no ecumenical sentence affirming the fact either that Honorius's letters to Sergius contain heresy, or that they were intended to define the question with which they deal. The sentence passed by the fathers of the council has ecumenical value only in so far as it was approved by Leo II; but, in approving the condemnation of Honorius, his successor adds the very important qualification that he is condemned, not for the doctrinal reason that he taught heresy, but on the moral ground that he was wanting in the vigilance expected from him in his Apostolic office and thereby allowed a heresy to make headway which he should have crushed in its beginnings.

Pope Vigilius

There is still less reason for trying to found an objection to papal infallibility on the wavering conduct of Pope Vigilius in connection with the controversy of the Three Chapters; and it is all the more needless to delay upon this instance as most modern opponents of the papal claims no longer appeal to it.

Galileo

As to the Galileo affair, it is quite enough to point out the fact that the condemnation of the heliocentric theory was the work of a fallible tribunal. The pope cannot delegate the exercise of his infallible authority to the Roman Congregations, and whatever issues formally in the name of any of these, even when approved and confirmed in the ordinary official way by the pope, does not pretend to be ex cathedra and infallible. The pope, of course, can convert doctrinal decisions of the Holy Office, which are not in themselves infallible, into ex cathedra papal pronouncements, but in doing so he must comply with the conditions already explained — which neither Paul V nor Urban VIII did in the Galileo case.

Conclusion

The broad fact, therefore, remains certain that no ex cathedra definition of any pope has ever been shown to be erroneous.
Mutual relations of the organs of infallibility

A few brief remarks under this head will serve to make the Catholic conception of ecclesiastical infallibility still clearer. Three organs have been mentioned:

the bishops dispersed throughout the world in union with the Holy See;
ecumenical councils under the headship of the pope; and
the pope himself separately.

Through the first of these is exercised what theologians describe as the ordinarium magisterium, i.e. the common or everyday teaching authority of the Church; through the second and third the magisterium solemne, or undeniably definitive authority. Practically speaking, at the present day, and for many centuries in the past, only the decisions of ecumenical councils and the ex cathedra teaching of the pope have been treated as strictly definitive in the canonical sense, and the function of the magisterium ordinarium has been concerned with the effective promulgation and maintenance of what has been formally defined by the magisterium solemne or may be legitimately deduced from its definitions.

Even the ordinarium magisterium is not independent of the pope. In other words, it is only bishops who are in corporate union with the pope, the Divinely constituted head and centre of Christ's mystical body, the one true Church, who have any claim to share in the charisma by which the infallibility of their morally unanimous teaching is divinely guaranteed according to the terms of Christ's promises. And as the pope's supremacy is also an essential factor in the constitution of an ecumenical council — and has in fact been the formal and determining factor in deciding the ecumenicity of those very councils whose authority is recognized by Eastern schismatics and Anglicans — it naturally occurs to enquire how conciliar infallibility is related to papal. Now this relation, in the Catholic view, may be explained briefly as follows:

Theories of conciliar and of papal infallibility do not logically stand or fall together, since in the Catholic view the co-operation and confirmation of the pope in his purely primatial capacity are necessary, according to the Divine constitution of the Church, for the ecumenicity and infallibility of a council. This has, de facto, been the formal test of ecumenicity; and it would be necessary even in the hypothesis that the pope himself were fallible. An infallible organ may be constituted by the head and members of a corporate body acting jointly although neither taken separately is infallible. Hence the pope teaching ex cathedra and an ecumenical council subject to the approbation of the pope as its head are distinct organs of infallibility.
Hence, also, the Gallican contention is excluded, that an ecumenical council is superior, either in jurisdiction or in doctrinal authority, to a certainly legitimate pope, and that one may appeal from the latter to the former. Nor is this conclusion contradicted by the fact that, for the purpose of putting an end to the Great Western Schism and securing a certainly legitimate pope, the Council of Constance deposed John XXIII, whose election was considered doubtful, the other probably legitimate claimant, Gregory XII, having resigned. This was what might be described as an extra-constitutional crisis; and, as the Church has a right in such circumstances to remove reasonable doubt and provide a pope whose claims would be indisputable, even an acephalous council, supported by the body of bishops throughout the world, was competent to meet this altogether exceptional emergency without thereby setting up a precedent that could be erected into a regular constitutional rule, as the Gallicans wrongly imagined.
A similar exceptional situation might arise were a pope to become a public heretic, i.e., were he publicly and officially to teach some doctrine clearly opposed to what has been defined as de fide catholicâ. But in this case many theologians hold that no formal sentence of deposition would be required, as, by becoming a public heretic, the pope would ipso facto cease to be pope. This, however, is a hypothetical case which has never actually occurred; even the case of Honorius, were it proved that he taught the Monothelite heresy, would not be a case in point.

Scope and object of infallibility
1

In the Vatican definition infallibility (whether of the Church at large or of the pope) is affirmed only in regard to doctrines of faith or morals; but within the province of faith and morals its scope is not limited to doctrines that have been formally revealed. This, however, is clearly understood to be what theologians call the direct and primary object of infallible authority: it was for the maintenance and interpretation and legitimate development of Christ's teaching that the Church was endowed with this charisma. But if this primary function is to be adequately and effectively discharged, it is clear that there must also be indirect and secondary objects to which infallibility extends, namely, doctrines and facts which, although they cannot strictly speaking be said to be revealed, are nevertheless so intimately connected with revealed truths that, were one free to deny the former, he would logically deny the latter and thus defeat the primary purpose for which infallibility was promised by Christ to His Church. This principle is expressly affirmed by the Vatican Council when it says that "the Church, which, together with the Apostolic office of teaching received the command to guard the deposit of faith, possesses also by Divine authority (divinitus) the right to condemn science falsely so called, lest anyone should be cheated by philosophy and vain conceit (cf. Colossians 2:8)" (Denz., 1798, old no. 1845).

2

Catholic theologians are agreed in recognising the general principle that has just been stated, but it cannot be said that they are equally unanimous in regard to the concrete applications of this principle. Yet it is generally held, and may be said to be theologically certain, (a) that what are technically described as "theological conclusions," i.e. inferences deduced from two premises, one of which is revealed and the other verified by reason, fall under the scope of the Church's infallible authority. (b) It is also generally held, and rightly, that questions of dogmatic fact, in regard to which definite certainty is required for the safe custody and interpretation of revealed truth, may be determined infallibly by the Church. Such questions, for example, would be: whether a certain pope is legitimate, or a certain council ecumenical, or whether objective heresy or error is taught in a certain book or other published document. This last point in particular figured prominently in the Jansenist controversy, the heretics contending that, while the famous five propositions attributed to Jansenius were rightly condemned, they did not truly express the doctrine contained in his book "Augustinus". Clement XI, in condemning this subterfuge (see Denz., 1350, old no. 1317) merely reasserted the principle which had been followed by the fathers of Nicaea in condemning the "Thalia" of Arius, by the fathers of Ephesus in condemning the writings of Nestorius, and by the Second Council of Constantinople in condemning the Three Chapters. (c) It is also commonly and rightly held that the Church is infallible in the canonization of saints, that is to say, when canonization takes place according to the solemn process that has been followed since the ninth century. Mere beatification, however, as distinguished from canonization, is not held to be infallible, and in canonization itself the only fact that is infallibly determined is that the soul of the canonized saint departed in the state of grace and already enjoys the beatific vision. (d) As to moral precepts or laws as distinct from moral doctrine, infallibility goes no farther than to protect the Church against passing universal laws which in principle would be immoral. It would be out of place to speak of infallibility in connection with the opportuneness or the administration of necessarily changing disciplinary laws although, of course, Catholics believe that the Church receives appropriate Divine guidance in this and in similar matters where practical spiritual wisdom is required.

What teaching is infallible?

A word or two under this head, summarizing what has been already explained in this and in other articles will suffice.

As regards matter, only doctrines of faith and morals, and facts so intimately connected with these as to require infallible determination, fall under the scope of infallible ecclesiastical teaching. These doctrines or facts need not necessarily be revealed; it is enough if the revealed deposit cannot be adequately and effectively guarded and explained, unless they are infallibly determined.

As to the organ of authority by which such doctrines or facts are determined, three possible organs exist. One of these, the magisterium ordinarium, is liable to be somewhat indefinite in its pronouncements and, as a consequence, practically ineffective as an organ. The other two, however, are adequately efficient organs, and when they definitively decide any question of faith or morals that may arise, no believer who pays due attention to Christ's promises can consistently refuse to assent with absolute and irrevocable certainty to their teaching.

But before being bound to give such an assent, the believer has a right to be certain that the teaching in question is definitive (since only definitive teaching is infallible); and the means by which the definitive intention, whether of a council or of the pope, may be recognized have been stated above. It need only be added here that not everything in a conciliar or papal pronouncement, in which some doctrine is defined, is to be treated as definitive and infallible. For example, in the lengthy Bull of Pius IX defining the Immaculate Conception the strictly definitive and infallible portion is comprised in a sentence or two; and the same is true in many cases in regard to conciliar decisions. The merely argumentative and justificatory statements embodied in definitive judgments, however true and authoritative they may be, are not covered by the guarantee of infallibility which attaches to the strictly definitive sentences — unless, indeed, their infallibility has been previously or subsequently established by an independent decision.