St Michael the Archangel

And there was a great battle in heaven, Michael and his angels fought with the dragon, and the dragon fought and his angels: And they prevailed not, neither was their place found any more in heaven.  And that great dragon was cast out, that old serpent, who is called the devil and Satan, who seduces the whole world; and he was cast unto the earth, and his angels were thrown down with him. And I heard a loud voice in heaven, saying: Now has come salvation, and strength, and the kingdom of our God, and the power of his Christ: because the accuser of our brethren is cast forth, who accused them before our God day and night. And they overcame him by the blood of the Lamb, and by the word of the testimony, and they loved not their lives unto death. Therefore rejoice, O heavens, and you that dwell therein. Woe to the earth, and to the sea, because the devil is come down unto you, having great wrath, knowing that he has but a short time. (Apocalypse 12:7-12)

St. Michael the Archangel, defend us in battle; be our defense against the wickedness and snares of the devil. May God rebuke him, we humbly pray. And do you, O prince of the heavenly host, by the power of God thrust into hell Satan and all the evil spirits who prowl about the world for the ruin of souls. Amen.