In almost all cases, the common liturgical celebration concludes with the dismissal proper to the Mass. Not too long ago, however, a special prayer to Saint Michael the Archangel was part of the conclusion of Mass.
Pope Leo XIII, in 1886, decreed that the prayer to St. Michael be recited at the end of low Mass, in addition to the Salve Regina. These prayers continued until the introduction of the new version of the Mass.
In 1994, Pope John Paul II requested the faithful to once again begin using the Prayer to St. Michael in the battle of our times “against the forces of darkness and against the spirit of this world.”
May prayer strengthen us for the spiritual battle we are told about in the Letter to the Ephesians, “Draw strength from the Lord and from his mighty power” (Eph 6 10). The Book of Revelation refers to this same battle recalling before our eyes the image of St. Michael the Archangel (Rev. 12:7). Pope Leo XIII certainly had a very vivid recollection of this scene when, at the end of the last century, he introduced a special prayer to St Michael throughout the Church. “St Michael the Archangel defend us in battle, be our safeguard against the wickedness and snares of the devil.” Although today this prayer is no longer recited at the end of Mass, I ask everyone not to forget it, and to recite it to obtain help in the battle against the forces of darkness and against the spirit of this world. (Pope John Paul II, Regina Caeli, 24 April 1994)
Even though this special prayer is no longer recited by the celebrant before concluding the Mass, it would be proper for the faithful, whether individuals or as small groups, to recite the Prayer to St. Michael before leaving the nave.
Saint 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, thrust into Hell, Satan and all the other evil spirits, who prowl throughout the world, seeking the ruin of souls. Amen.
Sancte Michael Archangele,
defende nos in proelio,
et insidias diaboli esto praesidium.
Imperet illi Deus,
Princeps militiae caelestis,
Satanam aliosque spiritus malignos,
qui ad perditionem animarum
pervagantur in mundo,
in infernum detrude. Amen.
God bless you,