72. Is then the outward washing with water itself the washing away of sins?

No, for only the blood of Jesus Christ and the Holy Spirit cleanse us from all sin

73. Why then does the Holy Spirit call Baptism the washing of regeneration and the washing away of sins?

God speaks thus not without great cause, namely, not only to teach us thereby that like as the filthiness of the body is taken away by water, so our sins are taken away by the blood and Spirit of Christ; but much more, that by this divine pledge and token He may assure us, that we are as really washed from our sins spiritually as our bodies are washed with water. (Heidelberg Catechism).

This has already been addressed repeatedly in previous posts since we began working through the section on the sacraments so there is no need to repeat all of that here. We need to understand two things:

1. The nature of signs
2. The teaching of Scripture as to how we are actually given new life

The Nature of Signs

In the nature of signs (and seals) they are not the thing represented and sealed. The embossed, stamped, and signed diploma is not one’s education nor is a marriage certificate one’s marriage. It has long been a great temptation to turn the sacramental signs and seals into the things signified and sealed. This is a form of rationalism because it makes the Christian faith just a little more reasonable to the natural mind. In contrast, Jesus seemed intent on confounding natural reason. This is why he said to Nicodemus: “You must be born again” (John 3:3–8). The Spirit grants life (Gen 1) and new life and his movements cannot be controlled by us nor can they be predicted. He is free to operate when and where he wills. We we, however, to say either that the Spirit is so embedded in the sacrament that it necessarily grants new life when the sacrament is administered or that the sacrament is otherwise infused with divine grace such that it necessarily (ex opere) grants new life then we shall have made the Christian faith that much less mysterious. Reformed Christians should remember this when we are criticized by “our Lutherans” (as Turretin wrote) for being “rationalist”—which is Lutheran code for, “does not agree with us.”

Nevertheless, contra those who would empty the sacraments of genuine spiritual power, we should say that because of the sacramental union (not identity) between the sign (and seal) and the thing signified, because there are divine promises attached to the sacraments, because the Spirit operates through the sacraments to accomplish his purposes it is utterly wrong to think of them as empty. They cannot be because they are instituted by Christ as part of the administration of his covenant of grace. That is the real question here: is the administration of the covenant of grace significant? Of course it is. Our Lord commanded Abraham to administer the sign and seal of the covenant of grace to believing adults and to their children (Gen 17:1–10). That command alone makes the administration of the covenant of grace significant. The visible covenant community is the place (locus) where God ordinarily grants saving faith. So, we are really discussing ecclesiology. Has Christ established a church? Again, the answer is yes. He has always had a visible, covenant people. The church was very small after the fall but it grew. He delivered his people through the flood and again out of Egypt, through the Red Sea, across the Jordan, and finally fulfilled all those types and shadows in the incarnation, obedience, death, and resurrection of Christ. Our Lord Jesus established a new covenant community in which he promised to continue to administer the covenant of grace. That is why Matthew chapters 16 and 18 are so important. The King has given to the visible church the keys of the kingdom (the preaching of the gospel and the administration of discipline; Heidelberg Catechism 83) and he has even given us instruction on how to use the keys. The use of the keys is the administration of the covenant of grace. Initiation in the covenant community of believers and their children (baptism) is an essential, divinely commanded element of the administration of the covenant of grace in the church.

The Teaching of Scripture

Second, Scripture clearly and repeatedly assigns the giving of new life and all that follows not to the sign and seal of the covenant of grace but to the Holy Spirit.

Baptism, which corresponds to this (ἀντίτυπον), 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… (1 Pet 3:21; ESV).

Peter expressly establishes an analogy and a close relationship between the sign and seal of baptism with regeneration (the granting of new life) but he does not identify them such that baptism is the granting of new life. Baptism itself does not save us. Baptism is the antitype of that which saves us, namely, the washing by the Spirit. How do we know this? Read the preceding verse:

because they formerly did not obey, 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 (1 Pet 3:20; ESV)

What is the frame of reference for baptism and washing? It is the flood. Did the flood save anyone? No. It condemned those who did not believe (an aspect of baptism sometimes neglected; there is a judicial aspect of baptism for the reprobate) but God’s people were saved out of the judgment by the ark. To what does the ark correspond? Christ. He is the ark. The Noahic baptismal flood was an antitype of Christ, who underwent the flood of judgment for us, and it testifies to our outward identity with Christ and to believers it signifies and seals that just as he suffered the judgment flood for us, as he was drowned in divine wrath, as it were, we have died with him and by his grace we have been redeemed.

In short the entire point of 1 Peter 3:21 is to teach precisely the opposite of what it is often construed to mean. It intends to teach that baptism does not necessarily save anyone to whom it is applied. The key here is to notice and understand what an antitype is: something from the past that points to, illustrates, and corresponds to something in the present. The antitype is between the Noahic flood, baptism, and Christ’s death for us and the judgment to come. Jesus uses the flood in a similar way in Matthew 24:39. “The flood came and took them all away.” Having established an analogy between the flood and judgment he applies it to the final judgment. This is why, if we follow his analogy carefully and correctly we must say that we do not want to be “taken” (in judgment) but we want to “left behind” in salvation. Hence the foolishness of all the Left Behind mania.

Paul teaches the same doctrine in Ephesians:

that he might sanctify her, having cleansed her by the washing of water with the word (Eph 5:26; ESV).

It is the Word or Christ’s Spirit operating through the Word, that washes and cleanses. Again, holy baptism is a sacrament, a sign and seal of what Christ does to and in us but it is not the thing signified. The Apostle John assigns our cleansing not to baptism but to the blood of Christ:

But if we walk in the light, as he is in the light, we have fellowship with one another, and the blood of Jesus his Son cleanses us from all sin (1 John 1:7; ESV).

This is judicial language drawn from the Old Testament. Baptism is a sign and seal to believers that as the blood of bulls of goats pointed forward to the reality of Christ’s final satisfaction of divine justice, so too we are clean. The blood of bulls and goats was sacramental. It did not make us clean. That’s why God repeatedly told the Israelites that he was not pleased with their sacrifices. What God demands is the reality and Christ is that reality for us and as a consequence of all he did, he, by his Spirit, is conforming us to that reality in progressive sanctification.

And such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God (1 Co 6:11; ESV).

That it is the Spirit of Christ who cleanses us is clear in 1 Corinthians 6. We were ungodly by nature but now, having been justified sola gratia, sola fide we are being progressively cleansed, which takes us back to Heidelberg 70 and the double benefit of Christ.

Baptism is not magic. It does not place us in a state of grace (acceptance with God) whereby we must cooperate with grace (or at least not resist lest we fall). No, baptism signifies that by the same power whereby he rescued Noah out of judgment and the Israelites out of Egypt, so too, he has finally redeemed us from the judgment to come by the once-for-all obedience and death of Christ and he is at work in us now, by his grace, to conform us to the image of Christ.

All the posts on the Heidelberg Catechism.