The Sign of the Cross
The simplest and most frequent Catholic prayer — a profession of faith in the Trinity traced on the body.
In the name of the Father, and of the Son, and of the Holy Spirit. Amen.
About this prayer
Touch your forehead at "Father," your chest at "Son," and your left then right shoulder at "Holy Spirit." Eastern Catholics touch the right shoulder first.
Christians have marked themselves with the cross since at least the second century; Tertullian (c. 200) wrote that believers made it "at every forward step and movement." It professes two mysteries at once: the Trinity, in the words, and our redemption, in the sign.