In many ways, this is the crux of the matter, because the practice of infant baptism—and many other New Testament doctrines, such as the Trinity and justification by faith—rests squarely on an Old Testament foundation. Remove that foundation, and infant baptism collapses.

How should we view the Old Testament? Should we reject it as having nothing to say to us today? Or should we obliterate all distinctions between the two Testaments? I believe that we should avoid both extremes. The Old Testament is related to the New in the way that a bud is related to a flower and an acorn is to an oak. The people of God in the Old Testament are compared to children; in the New they have come to adulthood. (Cf. Galatians 4:1-7.) Two extremes must be avoided as we deal with the Old and New Testaments: that of an extreme kind of Dispensationalism that sees little connection and continuity between the Old and New Testaments, on the one hand, and an approach that flattens Redemptive history, on the other, as if there were no true and radical significance to the Cross.

But how is the Old Testament fulfilled in the New? Let us take as an example the Old Testament celebration of the Passover. After having given elaborate instructions about selecting the Passover lamb, God told his people, “Obey these instructions as a lasting ordinance for you and your descendants.” (Exodus 12:24.) How are New Testament believers to carry out this commandment? Are we to slaughter lambs today, or are we simply to abandon the Passover ordinance completely? We are to celebrate it, says Paul, “For Christ, our Passover Lamb, has been sacrificed. Therefore let us keep the Festival. . . .” (1 Corinthians 5:7, 8.)

Christian people have continued to observe the Passover for almost two thousand years; they do it every time they break the bread and drink the wine in the Lord’s Supper. And just as Old Testament believers purged the leaven out of their houses, so we must purge out of our hearts “the old yeast, the yeast of malice and wickedness.” (1 Corinthians 5:8.)

As with other New Testament institutions, baptism does not exist simply as a New Testament phenomenon; it is the Spiritually enriched, outwardly modified continuation of an Old Testament ordinance, circumcision. What is the real meaning of circumcision, and how is it fulfilled in baptism? The most basic significance of circumcision lies in the historical fact that Jesus was circumcised for us. The real circumcision of Jesus did not occur when he was eight days old but in his thirty-third year. A rabbi’s knife did not carry it out, but iron spikes and a spear on a Roman cross.

When God made his gracious contract with Abraham, he cut (karath.), or established that covenant—not only with Abraham, but with his descendants as well. (Genesis 15:18.) In time God expounded on the meaning of that agreement in greater detail. His promises are sure to all who believe, but God warned that the one who does not respond to this contract “will be cut off (karath.) from his people; he has broken my covenant.” (Genesis 17:14.)

God gave an outward reminder and seal of confirmation of this covenant: “Every male among you shall be circumcised.” (Genesis 17:10.) They cut off the foreskin to remind the people of the blessings and obligations of the contract. It was a symbolic way of saying, “May I be cut off in damnation, if I do not live up to this covenant.”

The crucifixion of Christ is not only the reality of circumcision. It is also the reality of baptism. Jesus, in looking ahead to his death on the cross, asked James and John, “Can you drink the cup I drink or be baptized with the baptism I am baptized with?” (Mark 10:38 .) On the cross Jesus drank to the last bitter dregs the cup of God’s wrath. As our Savior hung on the cross, he was baptized with the judgment of a holy God against human sin. He was circumcised by the fury of divine justice as his life was cut off.

The Apostle Paul unites circumcision and baptism (the Old and New Testament signs of membership among God’s people.). After reminding the Gentiles of the total sufficiency of Christ to save them, Paul tells them: “In him you were also circumcised, in the putting off of the sinful nature, not with a circumcision done by the hands of men but with the circumcision done by Christ, having been buried with him in baptism and raised with him through your faith in the power of God, who raised him from the dead.” (Colossians 2:11, 12.)

When Jesus died on the cross, all believers in all ages, both Jew and Gentile, male and female, bond and free, were circumcised with him. So, too, were we all baptized with him. That is the connection between circumcision and baptism, the death of Christ on the cross for our sins.

Some people seem to think that circumcision was little more than a sign of national identification, a kind of glorified pledge of allegiance to the nation of Israel . Scripture, however, does give us a clear understanding of the significance of circumcision. Perhaps the fullest treatment on the subject is found in the Book of Romans. There Paul tells us: “A man is not a Jew if he is only one outwardly, nor is circumcision merely outward and physical. No, a man is a Jew if he is one inwardly; and circumcision is circumcision of the heart, by the Spirit, not by the written code.” (Romans 2:28, 29.) The meaning of circumcision, then, is not some outward thing; it points to the work of the Holy Spirit in giving a new heart. Circumcision reminds us of the individual’s need of being born a second time.

To be circumcised was to wear a sign that said, “I am a believer; I have been born again; God accepts me as holy and righteous; He has established his covenant promises with me.” It was to bear the seal of God’s ownership. To be circumcised was to say that Christ would die for your sins and to confess that you were united to him as he is offered in the gospel, the same gospel which was preached to Abraham. (Galatians 3:3.) Abraham was circumcised because he looked forward with rejoicing to the day of Christ. (John 8:56.)

What can be said about the real meaning of circumcision can be said about the real meaning of baptism, because baptism is New Testament circumcision. Under the New Covenant the gospel encompasses all nations and is not limited to one race as it was, for all practical purposes, under the Old Covenant. This is part of the reason why females also receive the seal of faith alongside males today. As with the other great symbol of the Old Testament, the Passover, so with circumcision: blood had to be shed. However, the death of Christ has fulfilled the shedding of blood, once for all time, on the cross. The outward form of circumcision is different from that of baptism, but the inward meaning is the same.

Whatever God’s reasons, we see that every objection which people have raised against infant baptism may also be raised against the practice of circumcision in the Old Testament. It is not our place to object to God’s commandments. It is our place to submit to his will in all things. Why did God command us to do this?

God told Abraham to place the mark of divine ownership on his household because it was God’s purpose for them to belong to him: “I will establish my covenant as an everlasting covenant between me and you and your descendants after you for the generations to come, to be your God and the God of your descendants after you.” (Genesis 17:7.) The Bible brings the same thought out hundreds of years later, on the plains of Moab, as God’s people were about to enter the promised land: “The Lord your God will circumcise your hearts and the hearts of your descendants, so that you may love him with all your heart and with all your soul, and live.” (Deuteronomy 30:6.) Deuteronomy 30:6 had both a present and a future meaning for Moses’ hearers.

Heart circumcision was very much the emphasis of the Old Covenant. Of the some six hundred cases where the Hebrew Bible uses the word, LEB, “heart,” a significant number of verses point to the need of a godly heart, one that could only exist after a heart was circumcised. The Old Testament itself indicates that there was an inner reality to circumcision that no one possessed simply because his prepuce was clipped. That is why Jeremiah admonished some physically circumcised descendants of Abraham that they needed to experience the reality of circumcision by means of a sovereign work of grace: “Circumcise yourselves to the LORD, circumcise your hearts, you men of Judah and people of Jerusalem, or my wrath will break out and burn like fire because of the evil you have done—burn with no one to quench it.” (Jeremiah 4:4.)

‘“The days are coming,” declares the LORD, “when I will punish all who are circumcised only in the flesh—Egypt, Judah, Edom, Ammon, Moab and all who live in the desert in distant places. For all these nations are really uncircumcised, and even the whole house of Israel is uncircumcised in heart.”’ (Jeremiah 9:25, 26.)