Communion Antiphon, Ps 117 (116):1, 2:O praise the Lord, all you nations, for his merciful love towards us is great. The Liturgy today is concerned with Baptism. Water by itself cannot cleanse leprosy; but God can use it to do so. If God can cleanse the leprosy of the body with water there is no reason why he cannot use it to wash leprosy of soul. The second point which the Liturgy intends to bring home to us is that God’s salvation is offered and available to all men who believe in his words and obey them. –St. Andrew Bible Missal