Isn’t the Bible clear enough on the necessity of baptism in water?
And as they went along the road they came to some water, and the eunuch said, “See, here is water! What is to prevent my being baptized?” … And he commanded the chariot to stop, and they both went down into the water, Philip and the eunuch, and he baptized him. (Acts 8:36, 38)
Philip did not say “you don’t need water to be baptized,” did he?
While Peter was still saying this, the Holy Spirit fell on all who heard the word. And the believers from among the circumcised who came with Peter were amazed, because the gift of the Holy Spirit had been poured out even on the Gentiles. For they heard them speaking in tongues and extolling God. Then Peter declared, “Can any one forbid water for baptizing these people who have received the Holy Spirit just as we have?” And he commanded them to be baptized in the name of Jesus Christ. Then they asked him to remain for some days. (Acts 10:44-48)
Notice that Peter commanded these Gentiles (who had received the Holy Spirit in an extraordinary manner) to be baptized. They did not request it first, or ask to do it as a public sign. They did it because it was required of them by St. Peter.
“Rise and be baptized, and wash away your sins.” (Acts 22:16)
St. Paul’s uses the phrase “wash away” in the retelling of his baptism, which, when put next to these other references, makes it clear that water is being spoken of. And he says that this baptism washes away sins, just like St. Peter declared in Acts 2:42: “be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins.”
… God’s patience waited in the days of Noah, during the building of the ark, in which a few, that is, eight persons, were saved through water. Baptism, which corresponds to this, now saves you, not as a removal of dirt from the body but as an appeal to God for a clear conscience, through the resurrection of Jesus Christ… (1 Peter 3:20-21)
More clear teaching from the Prince of the Apostles.
