Romans 4:12-13

Romans 4:12  New International Version

And he is then also the father of the circumcised who not only are circumcised but who also follow in the footsteps of the faith that our father Abraham had before he was circumcised.                                                        Romans 4:13  New International Version

It was not through the law that Abraham and his offspring received the promise that he would be heir of the world, but through the righteousness that comes by faith.