Charles Spurgeon Commentary Romans 4:11-12

"and he received the sign of circumcision, a seal of the righteousness of the faith which he had while he was in uncircumcision; that he might be the father of all them that believe, though they be in uncircumcision, that righteousness might be reckoned unto them; and the father of circumcision to them who not only are of the circumcision, but who also walk in the steps of that faith of our father Abraham which he had in uncircumcision." — Romans 4:11-12 (ASV)

And he received the sign of circumcision, a seal of the righteousness of the faith which he had yet being uncircumcised: that he might be the father of all them that believe, though they be not circumcised; that righteousness might be imputed unto them also: and the father of circumcision to them who are not of the circumcision only, but who also walk in the steps of that faith of our father Abraham, which he had being yet uncircumcised.

The vital question is not, "How were we born?" or "What rites and ceremonies have been practiced upon us?" but, "Do we believe in God? Have we true faith in God's Word? Are we trusting our souls to the keeping of God's Son?"