While both circumcision and baptism function as covenant signs, they belong to different covenants with distinct meanings—one marking national identity, the other spiritual rebirth. Baptism is not a direct replacement of circumcision, but a new sign that reflects personal faith and union with Christ in the New Covenant.
Circumcision was a physical sign of inclusion in the Abrahamic Covenant, marking the offspring of Abraham and setting them apart (Genesis 17:10–14). Baptism is a New Covenant ordinance given to believers as a sign of faith and identification with Christ’s death and resurrection (Romans 6:3–4). Some believe baptism directly replaces circumcision, pointing to verses like Colossians 2:11–12, but the parallel there is between spiritual circumcision and union with Christ—not between infant circumcision and infant baptism.
The Old Covenant marked the external nation of Israel; the New Covenant is for those who are inwardly born again (Jeremiah 31:33–34). Nowhere do we find infants baptized simply because of their parents’ faith, nor is baptism ever applied to unbelievers. Though both signs communicate belonging, baptism is a sign to be done after salvation, unlike circumcision which was a sign to be done before entry into the covenant. Baptism is not a one-to-one replacement for circumcision, but a new sign that points to a better covenant, based on a better promise.
Because baptism indicates that someone is saved and, thus, belongs to the New Covenant community, namely the church, a question arises: is baptism, then, an extension of circumcision, which indicated one belonged to the Old Testament community? If so, what is the connection and/or limitations of such a connection?
A particular Reformed Protestant tradition, known as Pedobaptist, sees a direct connection between the two signs. They argue that just like circumcision was a sign that one was part of the Israelite community, baptism is a sign of belonging to the church community. To this point, most would agree that there is at least a loose similarity between them. However, the Pedobaptist view goes further. They argue that just like there were unbelieving Israelites who were circumcised because their parents were Israelites, so also should the children of believers be baptized. This is why they baptize newborns and why they are called Pedobaptists, where “pedo” means “child” in Greek.
Note that while this practice is similar in form to Roman Catholicism’s baptism of infants, unlike Roman Catholicism, Pedobaptists do not believe the infant is saved or has original sin removed because of the baptism. Rather, they view it merely as a sign that shows that the child has been given special, providential access to God’s grace by being able to participate in church life because of his or her parents' belief in a way that most unbelievers do not have access. In short, the baptized child will grow up surrounded by believers who regularly influence him or her toward Christ.
However, as already seen, the New Testament pattern is that people are saved and then baptized. This is why, in contrast to Pedobaptists, many believers are called Credobaptists, where “credo” is a Latin word for “I believe.” That is, they argue for “believer’s baptism” as the only time baptism is to be performed.
Perhaps the strongest New Testament verse a Pedobaptist has to support his or her view of infant baptism is Acts 16:33. This is the account of a jailer who was saved after Paul and Silas did not attempt to escape after an earthquake (Acts 16:25–30). After being saved, we read, “[the jailer] took them the same hour of the night and washed their wounds; and he was baptized at once, he and all his family” (Acts 16:33). The argument is that “all his family” indicates that baptism was applied even to those who were unsaved but a part of the same household.
However, because Acts 16:33 is not a prescriptive passage (a passage explaining what to do), but rather descriptive (simply saying what happened), we need to be careful about allowing this passage to override other clear, prescriptive passages. However, even considering the argument at face-value, there’s a weakness in it. Just prior to Acts 16:33, Paul said, “Believe in the Lord Jesus, and you will be saved, you and your household” (Acts 16:31). Surely, Paul was not saying that if the jailer, alone, believed, then his household would also be saved. That would be directly contrary to the rest of the New Testament, which says that we are each individually guilty and individually responsible. Instead, Paul was simply expressing the hope that the jailer’s household would also believe. It is even probable that the household was present, given that they were no longer inside the prison, but outside, perhaps in the courtyard, with others listening in on this conversation. In any case, just like Paul could not be saying that everyone in the household would be saved if the jailer believed, he did not mean that unbelievers in the household were to be baptized. He simply meant that those of the household who believed were also to be baptized.
Another minor problem with the Pedobaptist view is that only males were circumcised, whereas both men and women are to be baptized. So, even conceptually, there’s a difference between these signs. They would argue that the New Testament expands the sign, but that is an argument based on the assumption that the two signs are the same.
Finally, in the Old Testament, circumcision was the means for entry into the covenant. For foreigners, for example, they could not enter the community unless they were physically circumcised. Conversely, baptism comes after one has already entered the church through faith. Rather than how one enters, it is how one identifies with the community he or she just entered. This also indicates a discontinuity between the two signs.
Though some traditions link baptism to circumcision as related covenantal signs, this comparison flattens important distinctions between the Old and New Covenants. Circumcision was applied to male infants as a marker of national and covenant identity, but it did not guarantee spiritual life or faith. In contrast, baptism is a sign of regeneration, applied to those who have believed and been united with Christ.
The shift from the physical to the spiritual is crucial. The Old Covenant had many outward elements—circumcision, dietary laws, priestly rituals—but the New Covenant centers on inward transformation and personal relationship with God. While both covenants had signs, the nature and application of those signs differ dramatically.
To treat baptism as a simple replacement of circumcision risks confusing covenant membership with true salvation. The New Testament never commands the baptism of infants, and it never suggests that one can belong to the New Covenant apart from faith.
This does not mean children are unimportant in God’s plan—they are to be taught, discipled, and loved—but the sign of the New Covenant belongs to those who believe. Baptism testifies not just to belonging in a family or community, but to spiritual rebirth and union with Christ.
Churches must carefully distinguish between shadow and substance, law and gospel, external signs and internal reality. Baptism, as an ordinance rooted in the finished work of Christ, must reflect the spiritual transformation it signifies.