First Peter 3:21—“Baptism . . . now saves you”—is a difficult passage. Even revered figures in history, the likes of Augustine, Martin Luther, and John Calvin, have said as much. To appreciate the interpretive challenges this verse provides, we need only to read through a few commentaries, and we will no doubt see a wide range of opinions on display.
One of the things we learn from difficult passages such this is that we need to hold our interpretations loosely. We shouldn’t fight to the death over our understanding of 1 Peter 3:21. It is in an altogether different category than, say, John 14:6: “I am the way, and the truth, and the life. No one comes to the Father except through me.” We cannot hold a wide range of opinions on John 14:6, at least not within the bounds of historic Christian orthodoxy, and that is why it is appropriate for us to take a stand in defending the truth of that passage in a way that it isn’t appropriate in regard to 1 Peter 3:21. Peter’s comments demand greater patience precisely because they are less clear.
With this in mind, we can rightly give ourselves to considering this passage—every word of which is God-breathed (see 2 Tim. 3:16) and, as such, warrants our careful attention. The first thing we can say about 1 Peter 3:21 is that the analogy of faith (which teaches that Scripture interprets Scripture) prevents us from understanding this verse as a reference to baptismal regeneration. Other Bible passages explicitly tell us that regeneration is grounded on the life, death, and resurrection of Christ and is a work of the Holy Spirit who, like the wind, “blows” when and where He wills (John 3:5, 8; Titus 3:5–6). Still other passages declare that we are not saved by the “will of man” or by “human . . . exertion,” which would obviously include baptism, but by God who “has mercy on whomever he wills” (John 1:12–13; Rom. 9:15–18). Regeneration, therefore, happens when God wants it to happen and not necessarily in the act of water baptism. What is more, the account of the thief on the cross teaches us that regeneration and baptism have no necessary temporal connection whatsoever (Luke 23:43).
The next thing we can say is that the analogy of faith also helps us see that 1 Peter 3:21 is not unique in terms of the language it uses. Several other Bible passages speak similarly in regard to the relationship between a sacrament and the thing that the sacrament signifies. I think immediately of Genesis 17:10, which states: “This is my covenant, which you shall keep. . . . Every male among you shall be circumcised.” Here the Lord so connects the sacrament of circumcision to the thing it signifies (i.e., the covenant) that He speaks of them coextensively. The whole of the covenant can be reduced to just one thing: circumcision.