Composed by Leo XIII after a private vision in 1884 and recited after every Mass until 1965 — now restored in many parishes for spiritual warfare.
Sancte Michael Archangele, defende nos in proelio; contra nequitiam et insidias diaboli esto praesidium. Imperet illi Deus, supplices deprecamur: tuque, Princeps militiae caelestis, Satanam aliosque spiritus malignos, qui ad perditionem animarum pervagantur in mundo, divina virtute in infernum detrude. Amen.
St. Michael the Archangel, defend us in battle; be our protection against the wickedness and snares of the devil. May God rebuke him, we humbly pray; and do thou, O Prince of the heavenly host, by the power of God, cast into hell Satan and all the evil spirits who prowl about the world seeking the ruin of souls. Amen.
After every Low Mass (1886–1965; restored in many parishes today); in spiritual warfare and exorcism.
On October 13, 1884 — thirty-three years to the day before the great Miracle of the Sun at Fatima — Pope Leo XIII finished celebrating Mass and stood at the altar of the Vatican as if in a trance. When he came to himself he was visibly shaken. He went directly to his office and wrote the prayer to St. Michael, ordering that it be added to the Leonine Prayers said after every Low Mass throughout the Roman Catholic world.
Tradition (substantiated by witnesses including the secretary of Pius XI, Cardinal Nasalli Rocca) reports that the pope had overheard a dialogue between Christ and Satan: Satan boasting that with enough time and power he could destroy the Church; Christ granting him a century. Leo wrote the prayer in response.
The Leonine Prayers (including the St. Michael Prayer) were suppressed in the liturgical reform of 1965. John Paul II in 1994 publicly invited all Catholics to resume the prayer; many parishes have restored it after every Mass since.
