Prayer to St. Michael

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.