The Following is an excerpt from the Inimitable Dom Gueranger's Liturgical Year on the Feast of Leo the Great who turned back the barbarian Huns at the gates of Rome.
Leo the First, a Tuscan by birth, governed the Church at the period when Attila, the king of the Huns, surnamed the Scourge of God, was invading Italy. Attila pillaged and burned the city of Aquieleia, which he took after a three years' siege. This done, he rushed on Rome like a wild firebrand. He had reached the place where the Mincio joins the Po, and was on the point of ordering his troops to pass the river, when he was met by Leo, who was moved with compassion at the misfortunes that were threatening Italy. Sush was his superhuman eloquence, that he induced Attila to retrace his steps. When asked by his people how it was that, contrary to his custom he had yielded such ready obedience to the demands of the Roman Pontiff, the king answered, that he beheld, whilst Leo was speaking, a personage clad in priestly robes, who stood near, with a naked sword in his hand, and threatened him with death unless he obeyed the Pontiff., Whereupon he returned to Pannonia.
The Greek Church, in her Menaea, has an office in honour of St. Leo: we take from it the following stanzas. As they were composed before the Schism, they show us that the ancient Church of Constinatinople believed the supremacy of the Roman pontiff, and that it is not the Latins that have changed the faith. The Greeks keep the Feast of St. Leo on February 18.
O happy Pontiff ! glorious Leo ! thous has been made companion of the faithful priests and martyrs: for thou wast most invincible in battle, and immovable as a tower and fortress of religion. Thou didst proclaim, with most perfect orthodoxy and wisdom, the unspeakable generation of Christ.
O ruler of orthodoxy, teacher of religion and holiness, light of the whole earth, divinely insired glory of true believers, wise Leo ! thou enlightenest all men by thy teachings, O harp of the Holy Ghost !
Heir of the See of Peter, the Prince of the Apostles, thou didst prexside over the Church: thou hadst his spirit, and wast inflamed with zeal for the faith.
Beaming with most bright light, thou, O holy Leo, didst admirably preach the ineffable and divine incarnation, teaching the two natures, and the two wills of the Incarnate God.
Resplendent with the knowledge of divine truths, thou didst scatter on all sides the brightness of orthodoxy, and dispel the darkness of heresy. Departing this life, thou, O blessed one ! now dwellest in the light that knows no setting.
O inspired minister of God's mysteries thou didst admirably preach that Christ is the Only Son and Lord, begotten of the Father before all ages, born for us of the Virgin, and dwelling on earth like unto us.
Seated with glory upon the throne of the pontificate, thou didest stop the mouths of lions, and madest to shine upon thy flock the light of the knowledge of God, by proclaiming the divine dogma of the adorable Trinity. therefore has thou been glorified as a holy Pontiff initiated in the grace of God.
Thou, as a dazzling sun, didst rise in the West and wisely dispel the error of Eutyches, who mingled and confused the two natures, and that of Nestorius, who divided them as though they were two Persons. Thou taughtest us to adore one Christ in two natures, inseparably, interchangeably, unconfusedly united.
Inspired of God, thou didst appear to the people of God as another Moses, showing them the commandments of religion written, as it were, on tables. Thou didst explain in the assembly of the venerable masters: 'Praise, O ye priests ! and bless, and extol Christ for ever.'
Now, O priest of Christ ! thou art brightly decked with crown of beauty. As a faithful priest, thou has put on justice. Pray unceasingly for thy flock, now that thou has entered into the admirable joy of the Paradise of delights.
Thou, O most blessed Leo ! has worthily entered the abode where are the seats and throne and ranks of patriarch : thou hast entered as a true patriarch, all resplendent with faith and grace. Therefore do we all celebrate thy name for ever.