The "Vexilla Regis" is a Latin hymn in long metre by the Christian poet and Saint Venantius Fortunatus, Bishop of Poitiers. It takes its title from its opening stanza: Vexilla regis prodeunt, fulget crucis mysterium, quo carne carnis conditor suspensus est patibulo. The Banners of the King issue forth, the mystery of the Cross does gleam, where the Creator of flesh, in the flesh, by the cross-bar is hung.
The hymn was first sung in the procession (November 19, 569) when a relic of the True Cross, sent by the Byzantine Emperor Justin II from the East at the request of St. Radegunda, was carried in great pomp from Tours to her monastery of Saint-Croix at Poitiers. Its original processional use is commemorated in the Roman Missal on Good Friday, when the Blessed Sacrament is carried in procession from the Repository to the High Altar. Its principal use however, is in the Divine Office, the Roman Breviary assigning it to Vespers from the Saturday before Passion Sunday daily to Maundy Thursday, and to Vespers of feast of the Exaltation of the Holy Cross (September 14), and in pre-Vatican II breviary also for the feast of the Finding (May 3), and of the Triumph of the Holy Cross (July 16).
"So let us be confident, let us not be unprepared, let us not be outflanked, let us be wise, vigilant, fighting against those who are trying to tear the faith out of our souls and morality out of our hearts, so that we may remain Catholics, remain united to the Blessed Virgin Mary, remain united to the Roman Catholic Church, remain faithful children of the Church."- Archbp. Lefebvre 1980