In Reformed Covenant Theology, why does the covenant sign of circumcision pass away but the Abrahamic covenant of which it was the sign of does not?

Question

Galatians 3:16-18 denies that the Mosaic covenant annulled the promises of the Abrahamic and proceeds to argue the Christian gospel on the basis of the Abrahamic covenant against the idea of salvation by keeping the Mosaic law.

Yet, when the covenant was initially made with Abraham, God gave circumcision as the sign. Circumcision was given to Abraham (Genesis 17), not Moses (Exodus 34). Yet, in Paul especially, circumcision is often associated and even identified with the law of Moses in distinction to salvation by faith.

Paul seems emphatic that circumcision is not necessary and that trusting in circumcision is dangerous. It is easy to see why Paul would warn against trusting in works of the law given through Moses, but it is easy to sympathize with someone who feared the prospect of uncircumcision.

Genesis 17:14 Any uncircumcised male who is not circumcised in the flesh of his foreskin shall be cut off from his people; he has broken my covenant.

(Again, speaking to Abraham, not Moses).

Paul is not alone in his interpretation. It is also the verdict of the Jerusalem council in Acts 15, affirmed by none other than Peter himself. In Acts 15, they associate circumcision with a "custom of Moses" (v. 1 and 5 by the pro-circumcision men from Judea and Pharisees, and again in v. 10 when Peter indirectly refers to it as a yoke).

The bow placed in the sky in the Noahic covenant remains because the covenant with creation remains, summer and winter, seedtime and harvest. So it is reasonable to believe that even very ancient covenant signs that came before the advent of Christ could still be in effect if their corresponding covenants remain in effect.

Why is circumcision then associated with Moses and therefore part of the burden of the law? Clearly, Reformed Covenant Theology accepts the New Testament canon containing the Pauline epistles and Acts as scripture, and so we can understand this view to be correct on the basis of authority. I would just like a better explanation than I have for why this sign has passed away or been swallowed up by Moses. For context, I am a Reformed Christian who affirms Reformed Covenant Theology.

Answer 1

The Heidelberg Catechism says that baptism has replaced circumcision. (Emphasis mine).

Q & A 74

Q. Should infants also be baptized?

A. Yes. Infants as well as adults are included in God’s covenant and people, and they, no less than adults, are promised deliverance from sin through Christ’s blood and the Holy Spirit who produces faith. Therefore, by baptism, the sign of the covenant, they too should be incorporated into the Christian church and distinguished from the children of unbelievers. This was done in the Old Testament by circumcision, which was replaced in the New Testament by baptism.

Bannerman in The Church of Christ II, p. 98 says the following:

Circumcision was independent either of the introduction or abolition of the law of Moses, and would have continued the standing ordinance for admission into the Church of God as the seal of the covenant of grace, had not baptism been expressly appointed as a substitute for it."

Pierre C.H. Marcel in The Biblical Doctrine of Infant Baptism, p. 157 says the following:

One may admit that during the Mosaic period circumcision acquired a certain typical significance. But originally it was a sign and seal of the covenant which was made with Abraham. In so far as it was a type, it naturally vanished with the appearance of the anti-type, and even in so far as it was the seal of the covenant it gave place to an unbloody sacrament expressly instituted by Jesus Christ for the Church, and recognized as such by the Apostles, for, thanks to His work of redemption, Christ put an end once for all to the shedding of blood.

For the second part of the question, namely, why circumcision is associated with the law of Moses by the Judaizers, the answer is simple. Circumcision is part of the Mosaic law! While it is true that circumcision was first inaugurated with Abraham, it is repeated in the law of Moses. Jesus mentions this in John 7:22-23:

Moses gave you circumcision (not that it is from Moses, but from the fathers), and you circumcise a man on the Sabbath. If on the Sabbath a man receives circumcision, so that the law of Moses may not be broken, are you angry with me because on the Sabbath I made a man's whole body well?

So the Judaizers aren't exactly incorrect to associate circumcision with Moses, even though Moses was not the first to circumcise.

Answer 2

Circumcision didn't pass away; it blossomed from a physical act into a spiritual reality. The NT insists on a circumcised heart; without it there is no salvation. What was a sign - cutting off flesh - became a living reality as the Holy Spirit circumcises the heart. Even though we can't immediately see the results of the Spirit-heart circumcision, it is more real and effective than the physical act. Abraham was changed. His name was changed, and his body was changed. These were tangible effects of a real inward change.

One interesting sidenote, while we aren't sure of the precise origin of the word covenant, it might derive from the same word family for cut. The idea of covenant is introduced with God passing through the cut animals in Gen. 15.