Now this I say: The law, which came four hundred and thirty years after, does not put an end to the agreement made before by God, so as to make the undertaking without effect.
And he made with him the agreement of which circumcision was the sign. And so Abraham had a son, Isaac, and gave him circumcision on the eighth day; and Isaac had a son, Jacob, and Jacob was the father of the twelve heads of the families of Israel.