This is the Latin name given to the prayer of Simeon, who encounters Mary, Joseph, and the baby Jesus in the temple and recognizes that the child is the Messiah he has waited for all his life. Luke 2:29–32 says, “Lord, now You are letting Your servant depart in peace, according to Your word; for my eyes have seen Your salvation.” It has been widely used in church services and has been set to music.
See 620 (presentation of the Lord.)