The Third Week of Easter

"For just as, after the waters of the deluge, by which the old iniquity was purged, after the baptism, so to say, of the world, a dove was the herald which announced to the earth the assuagement of celestial wrath, when she had been sent her way out of the ark, and had returned with the olive branch, as sign which even among the nations is the foretoken of peace; so that by the self-same law of heavenly effect, to earth, that is, to our flesh, as it emerges from the font, flies the dove of the Holy Spirit, bringing us the peace of God sent out from the heavens."

Tertullian, Third Century