A fresco said to be of the Patriarchs, Abraham, Isaac and Jacob
Here I suggest that circumcision has to do with that strand of the promise to Abraham that pertains to the nation-state of Israel, covered by 'the land' of the Abrahamic covenant, temporary, and which once it became perverted into a scheme of ‘works righteousness’, was futile and doomed. Paul states in Galatians 5 that accepting circumcision as a necessity commits you to keeping the whole law as a means of salvation. ‘I testify again to every man who accepts circumcision [as obligatory for the Christian, and not as typifying the putting off of the flesh] that he is obligated to keep the whole law’. (5.2) Rather, what is required is what in his free grace the Lord gives, the circumcision of the heart. (Rom.1.29) The temporal order of things is important. Circumcision was instituted after the inauguration of the Abrahamic covenant, the law came after the promise, Moses came after Abraham.
The centre of gravity
But the difference which is surely the most striking is that by the time of the coming of Christ the terms of the new covenant of Jeremiah 31.31 are not yet fulfilled, not until Christ’s death and resurrection. He is the covenant head and testator. Without and until the death of the testator the deed is not done (Hebrews chs 9, 10.). The centre of gravity of the covenant of grace is placed firmly in the messianic era. What enables a situation in which all shall be taught of God. (John 6.45). and the sins of men and women, of Jew and Gentile, shall be remembered no more? The answer is the death of the testator of the covenant, which occurred in the death and resurrection of the testator, Christ, according to the Letter to the Hebrews.