Why Does 1 Peter 3:21 Say Baptism “Saves You”?

Does 1 Peter 3:21 teach that baptism is necessary in some way for salvation? Today, Derek Thomas poses important principles for interpreting the Bible’s language regarding the sacraments, including this challenging verse.

NATHAN W. BINGHAM: Joining us this week is the Chancellor's Professor of Systematic and Pastoral Theology at Reformed Theological Seminary. He also serves as one of the Ligonier's teaching fellows, Dr. Derek Thomas. Dr. Thomas, in 1 Peter 3:21, why does Peter say baptism saves you?

DR. DEREK THOMAS: Right. The full verse is "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." Let me put it this way. This is one of those verses"and pride and everything notwithstanding here"but if you and I were writing this, we wouldn't write it this way because it appears as though Peter might be saying something along the lines of baptismal regeneration. And in the history of the church, that is most certainly how it has been interpreted, that at the time of baptism, the Holy Spirit works in and through that physical act to actually regenerate. And there are ministers that I've heard, who have held babies up in the air and said something like, "This child is now a Christian," whatever that means.

But I think that what is taking place here is a subtlety that the Reformers were certainly aware of and that the divines at Westminster in the Westminster Confession were aware of. And I'm going to quote from chapter 27 of the Westminster Confession because chapter 27 is a general chapter about sacraments. And then there are two chapters, one on baptism, one on the Lord's Supper, but in the general chapter on sacraments, we read this in section 2: "There is, in every sacrament, a spiritual relation, or sacramental union""and that's code language""sacramental union between the sign and the thing signified: whence it comes to pass, that the names and effects of the one are attributed to the other."

Now, what is baptism? Baptism is a sign and seal not of faith but to faith of the gospel. It's a sign and seal to faith of regeneration. It's a sign and seal to faith of the assurance of salvation. It's a sign and seal to faith that our names are written in the Lamb's Book of Life. It's a sign and seal to faith of our election, our eventual homecoming to glory. So, it's not baptism that saves. It's what baptism is a sign and seal of"namely, faith and repentance and adoption, regeneration, not in that order. Resurrection, right? So, I think how the Reformers and Westminster divines understood what Peter is doing here and similar language about Jesus and the supper""This is My body; this is My blood""it's a sacramental union that the one is so closely identified with the other that, as it says, the effects of the one are attributed to the other. It's like Acts 20, which isn't about sacraments, but where Paul in his farewell address to the elders at Ephesus at Miletus speaks of the blood of God, right? Well, God doesn't have blood. It's Jesus that has blood and it's Jesus' physical nature, His human nature that has blood. But the one is so identified with the other that the effects of the one are attributed to the other. It's the principle of the sacramental union.