God made a covenant with Abraham that is recorded in Genesis 17. Just as a man-made covenant is made between two (or more) parties, and each party has an obligation to carry out, so there were two sides to this covenant.
God’s part
The first part of the covenant was the commitment to be carried out by God. He promised to make Abram a father of many nations (and changed his name to “Abraham” to reflect that); He promised kings would be of Abraham’s seed; the covenant would be an everlasting one; that the whole land of Canaan would be given to both Abraham and to his seed; that the possession of the land would not have a time limit and that He would be the God of both Abraham and of his seed.
Man’s part
The second part of the covenant was the part Abraham and his seed were to carry out — circumcision. Here was a physical act of cutting off flesh that was to express their intent to ally themselves with God and His covenant. With particular regard to Abraham, this act represented a seal of his righteousness which was by faith (Rom 4:11) — that is, a physical, visible sign of the state of his heart.
God declared that this act of circumcision was to go on from generation to generation — an everlasting covenant. The seriousness was stressed by the fact that whoever did not become physically circumcised would be cut off from the people of God. The reason for that is obvious: by not being circumcised, the man would be making a physical, visible statement that he did not ally himself with God and His covenant; he was declaring he would not cut off sinful flesh, and he could therefore not be a part of God’s covenant people.
Ritual kept, meaning lost
The problem started when the people became so intent on keeping the physical mark of the covenant, that they forgot the importance of the faith and love which prompted God to make the covenant with Abraham in the first place. Their betrayal of the spirit of the covenant became so great that Paul was later to say in Rom. 2:28, 29 (NIV) “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.” Paul says again in Rom. 4:12 (NIV) “And he is also the father of the circumcised who not only are circumcised but who also walk in the footsteps of the faith that our father Abraham had before he was circumcised.”
Our situation
We, under the new covenant, are no longer required to be physically circumcised, but there is still a physical act that God requires as a visible witness to the fact that we ally ourselves with God, and with His Son — who spiritually, and ultimately in his death, cut off the flesh and allied himself with his Father’s covenant. That physical act is baptism which shows that we, too, are allying ourselves with God and are willing to put away the things of the flesh. By so joining with Christ, we become “Abraham’s seed, and heirs according to the promise” (Gal. 3:29 NIV). We are thus part of the “many nations” of whom Abraham is the spiritual father. We can rejoice in the promise of God that He is our God, and look forward to the day when we may dwell in the land forever.
We must not, however, after the act of baptism, self-righteously rest on our laurels as the Jews did, but continuously grow in faith and love, walking in the footsteps of the faith of Abraham, until we, by God’s grace, join him at the marriage supper of the Lamb.
The Origin of the Organic World – Part One