ISB ~ Matthew 3 v11

I baptize you:John’s baptism differed from sacramental Baptism, which confers forgiveness and the regenerating grace of justifying faith (Acts 2:38). His was a visible token of repentance and preparation for the Messiah (cf. Is 1:16; Heb 9:10; CCC 718).

with water:John administered a baptism by water alone as a sign of purification. But as was shown in Noah’s day, water alone cannot cleanse the soul; the sinfulness of man’s heart remained unchanged even after the flood (Gen 6:5; 8:21). Only the Sacrament of Baptism infuses the Holy Spirit (Jn 3:5) and marks one’s adoption into God’s family (28:19) (CCC 1265).

with fire:A symbol of God and his purifying judgment (Deut 4:24; Sir 2:5; Is 4:3-5; Acts 2:3-4; CCC 696).