innumerable offspring to Abraham (Gen 12:1–3). God’s covenant with Abraham could only be realized by miraculous intervention. The miraculous nature of Isaac’s birth is the key to understanding circumcision as the sign of the covenant. After God made His promise to Abraham, every male member of Abraham’s household was required to be circumcised (Gen 17:15–27). Every male—and every woman, since the males were all incapacitated for a time—knew that circumcision was connected to God’s promise. It probably