Romans 4:11-12

Moffatt(i) 11 He only got circumcision as a sign or seal of the righteousness which belonged to his faith as an uncircumcised man. The object of this was to make him the father of all who believe as uncircumcised persons and thus have righteousness counted to them, 12 as well as a father of those circumcised persons who not only share circumcision but walk in the steps of the faith which our father Abraham had as an uncircumcised man.