Romans 4:11-13

11And he received the sign of circumcision as a seal of the righteousness of the trust he had while he was uncircumcised, so he might be the father of all who are trusting while uncircumcised—that righteousness might be credited to them as well.

12Also he is the father of the circumcised, to those not only circumcised but also walking in the footsteps of the trust of our father Abraham before his circumcision.

13For the promise to Abraham or to his seed—to become heir of the world—was not through law, but through the righteousness based on trust.