God gave Abraham circumcision as the sign of the covenant, a cutting in the flesh of every male in his house. But Abraham had already believed and been counted righteous years earlier, so the sign sealed a righteousness he already possessed by faith. The prophets therefore called for a circumcision of the heart, and Paul says believers receive the circumcision made without hands in Christ.
Not a summary of these passages: the passages themselves. Read them, then come back to the study below.
The study
What the Scripture says
1
The sign came after the faith
Abraham believed God in Genesis 15 and it was reckoned to him as righteousness. Circumcision was given in Genesis 17, years later. Paul builds his whole argument on that sequence: Abraham received the sign of circumcision as a seal of the righteousness of the faith he had while he was still uncircumcised, so that he might be the father of all who believe without being circumcised.
He believed in Yahweh; and he reckoned it to him for righteousness.And he believed in the Lord; and he counted it to him for righteousness.
This is my covenant, which you shall keep, between me and you and your seed after you. Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskin. It will be a token of the covenant between me and you.This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised. And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.
He received the sign of circumcision, a seal of the righteousness of the faith which he had while he was in uncircumcision, that he might be the father of all those who believe, though they might be in uncircumcision, that righteousness might also be accounted to them.And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also:
A seal does not create the document it authenticates; it certifies it. Circumcision marked Abraham and his household as participants in a covenant that rested on God's promise and Abraham's faith. That is why the sign could be given to infants who had not yet believed: it was a family mark of belonging to a covenant people, not a personal achievement to be earned.
You shall be circumcised in the flesh of your foreskin. It will be a token of the covenant between me and you.And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.
I will establish my covenant between me and you and your seed after you throughout their generations for an everlasting covenant, to be a God to you and to your seed after you.And I will establish my covenant between me and thee and thy seed after thee in their generations for an everlasting covenant, to be a God unto thee, and to thy seed after thee.
Moses told Israel to circumcise the foreskin of their heart and to stop being stiff-necked, and later promised that Yahweh Himself would circumcise their heart so that they could love Him. Jeremiah repeated the call. The outward sign was never meant to stand alone; a marked body with an uncircumcised heart was the very hypocrisy the prophets condemned.
Circumcise therefore the foreskin of your heart, and be no more stiff-necked.Circumcise therefore the foreskin of your heart, and be no more stiffnecked.
Yahweh your God will circumcise your heart, and the heart of your seed, to love Yahweh your God with all your heart, and with all your soul, that you may live.And the Lord thy God will circumcise thine heart, and the heart of thy seed, to love the Lord thy God with all thine heart, and with all thy soul, that thou mayest live.
Circumcise yourselves to Yahweh, and take away the foreskins of your heart, you men of Judah and inhabitants of Jerusalem; lest my wrath go out like fire, and burn so that no one can quench it, because of the evil of your doings.Circumcise yourselves to the Lord, and take away the foreskins of your heart, ye men of Judah and inhabitants of Jerusalem: lest my fury come forth like fire, and burn that none can quench it, because of the evil of your doings.
Paul says believers were circumcised with a circumcision not made with hands, in the putting off of the body of the sins of the flesh, in the circumcision of Christ, having been buried with Him in baptism and raised with Him through faith. What the sign pointed at is accomplished at the cross and applied to the believer, which is why the physical rite is no longer the mark of God's people.
in whom you were also circumcised with a circumcision not made with hands, in the putting off of the body of the sins of the flesh, in the circumcision of Christ; having been buried with him in baptism, in which you were also raised with him through faith in the working of God, who raised him from the dead.In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead.
But this is the covenant that I will make with the house of Israel after those days, says Yahweh: I will put my law in their inward parts, and in their heart will I write it; and I will be their God, and they shall be my people:But this shall be the covenant that I will make with the house of Israel; After those days, saith the Lord, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people.
This is my covenant, which you shall keep, between me and you and your seed after you. Every male among you shall be circumcised. You shall be circumcised in the flesh of your foreskin. It will be a token of the covenant between me and you.This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised. And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you.
He received the sign of circumcision, a seal of the righteousness of the faith which he had while he was in uncircumcision, that he might be the father of all those who believe, though they might be in uncircumcision, that righteousness might also be accounted to them.And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also:
Yahweh your God will circumcise your heart, and the heart of your seed, to love Yahweh your God with all your heart, and with all your soul, that you may live.And the Lord thy God will circumcise thine heart, and the heart of thy seed, to love the Lord thy God with all thine heart, and with all thy soul, that thou mayest live.
in whom you were also circumcised with a circumcision not made with hands, in the putting off of the body of the sins of the flesh, in the circumcision of Christ; having been buried with him in baptism, in which you were also raised with him through faith in the working of God, who raised him from the dead.In whom also ye are circumcised with the circumcision made without hands, in putting off the body of the sins of the flesh by the circumcision of Christ: Buried with him in baptism, wherein also ye are risen with him through the faith of the operation of God, who hath raised him from the dead.