Augustine of Hippo

After his resurrection, when he first appeared to his disciples, he said to them, "Receive the Holy Spirit." About this giving, then, it was said, "The Spirit had not yet been given because Jesus had not yet been glorified." "And he breathed upon their face." The One who first gave life to man by breathing and raised him up from the mire and by breathing gave a soul to his members is the same One who breathed upon their face that they might rise up from the slime and renounce filthy works.