“Amen, amen I say to thee, unless a man be born again of water and the Holy Ghost, he cannot enter into the kingdom of God.” (John 3:5)
Baptism is the first Sacrament received and its effects are threefold.
1.) Baptism cleanses us of original sin.
2.) Baptism cleanses us of personal sin if we were baptized at an older age.
3.) Baptism makes as members of Christ’s body the Church.
The effects of Baptism are not merely a symbol as Baptists and other groups claim; they are sacramental. We already see in the early Church that Christians believed in baptismal regeneration. The Scripture says God “saved us, by the laver of regeneration, and renovation of the Holy Ghost” (cf. Titus 3:5). The Church Fathers can attest to this.
“Then they are brought by us where there is water, and are regenerated in the same manner in which we were ourselves regenerated. For, in the name of God, the Father and Lord of the universe, and of our Saviour Jesus Christ, and of the Holy Spirit, they then receive the washing with water. For Christ also said, ‘Unless you be born again, you shall not enter into the kingdom of heaven.'” ~ Saint Justin Martyr (First Apology, ch. 61)
Not only do we see a clear reference to the Trinitarian formula, which will be explained in depth later, but we see the effects of Baptism. Saint Justin says the are brought “where there is water” and there “regenerated . . . in the name of God, the Father . . . and of our Saviour Jesus Christ, and of the Holy Spirit”, and so they “obtain in the water the remission of sins formerly committed”. Saint Irenaeus of Lyons adds that Baptism “is regeneration to God” (cf. Against Heresies 1:21). He includes “our bodies have received unity among themselves by means of that laver which leads to incorruption; but our souls by means of the Spirit” (ibid, 3:17). Saint Theophilus of Antioch wrote that “the things proceeding from the waters were blessed by God, that this also might be a sign of men’s being destined to receive repentance and remission of sins, through the water and laver of regeneration” (cf. Letter to Autolycus, bk. 2). Going back to Scripture, Baptism is foreshadowed by the floods in which it says, “This prefigured baptism, . . . saves you now” (1 Peter 3:21).