“baptism now saves you.” —St. Paul, oops St Peter, referenced by St_Thomas_Aquinas
Actually, the passage reads:
“...when God’s patience waited in the days of Noah, while the ark was being prepared, in which a few, that is, eight persons, were brought safely through water. 21 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 good conscience, through the resurrection of Jesus Christ...”
Baptism saves you in the corresponding sense in which the Flood saved Noah. Did the Flood save Noah’s life? Hardly! It would have killed him, had God not warned him to build the Ark. So in what sense did the Flood ‘save’ Noah?
It saved him from the surrounding world of sin. It separated him & his family from the sinful society in which they lived.
Salvation covers both justification (our being forgiven and given new life) and sanctification (become separated to God, to be made holy). Water baptism is an important part of sanctification. Like the Flood separating Noah - as St Peter said - so does water baptism separate us from the society around us.
John the Baptist said he baptized with water, but that Jesus would baptize with the Holy Spirit. Paul affirms this, writing, “For in one Spirit we were all baptized into one body—Jews or Greeks, slaves or free—and all were made to drink of one Spirit.”
We become a part of Christ - a part of the tribe of Christ, so to speak - when Jesus baptizes us with the Holy Spirit, giving us new life. Water baptism, done by man, is the appeal to God for a new life, separate from the life of the world around us. It is “an appeal to God for a good conscience” - and as Peter wrote a couple of sentences before: “having a good conscience, so that, when you are slandered, those who revile your good behavior in Christ may be put to shame”.
Water baptism is us asking God to let us live a new life of good behavior, one dedicated to Him and not to us. And Robertson notes that the word used is a rare one, used to describe an appeal - a request - that has already been granted.
I’m not discussing Catholicism here. I gave the same response recently on a thread from a “Church of Christ” person saying water baptism was required. It is the same answer I was given when I talked to a Baptist preacher in Logan Utah years ago, when a person from the “Church of Christ” told me I needed water baptism to become a Christian (and I had been baptized with water some years earlier, actually).
18And Jesus came up and spoke to them, saying, "All authority has been given to Me in heaven and on earth. 19"Go therefore and make disciples of all the nations, baptizing them in the name of the Father and the Son and the Holy Spirit, 20teaching them to observe all that I commanded you; and lo, I am with you always, even to the end of the age."Jesus didn't instruct his disciples to hand out Bibles, tell people to recite the sinner's prayer, or to make a confession of faith alone, although He could have. Jesus focused on two things: Baptism and Apostolic Teaching (which can be oral or written [i.e., Scripture]). The reception of both are normative for discipleship.
VI. THE NECESSITY OF BAPTISMMore from the Catechism.1257 The Lord himself affirms that Baptism is necessary for salvation.60 He also commands his disciples to proclaim the Gospel to all nations and to baptize them.61 Baptism is necessary for salvation for those to whom the Gospel has been proclaimed and who have had the possibility of asking for this sacrament.62 The Church does not know of any means other than Baptism that assures entry into eternal beatitude; this is why she takes care not to neglect the mission she has received from the Lord to see that all who can be baptized are "reborn of water and the Spirit." God has bound salvation to the sacrament of Baptism, but he himself is not bound by his sacraments.
CCC
Baptism in the Church1226 From the very day of Pentecost the Church has celebrated and administered holy Baptism. Indeed St. Peter declares to the crowd astounded by his preaching: "Repent, and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins; and you shall receive the gift of the Holy Spirit."26 The apostles and their collaborators offer Baptism to anyone who believed in Jesus: Jews, the God-fearing, pagans.27 Always, Baptism is seen as connected with faith: "Believe in the Lord Jesus, and you will be saved, you and your household," St. Paul declared to his jailer in Philippi. And the narrative continues, the jailer "was baptized at once, with all his family."28
1227 According to the Apostle Paul, the believer enters through Baptism into communion with Christ's death, is buried with him, and rises with him:
Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.29
The baptized have "put on Christ."30 Through the Holy Spirit, Baptism is a bath that purifies, justifies, and sanctifies.31
1228 Hence Baptism is a bath of water in which the "imperishable seed" of the Word of God produces its life-giving effect.32 St. Augustine says of Baptism: "The word is brought to the material element, and it becomes a sacrament."33