12 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.
English Standard Version
12 and to make him the father of the circumcised who are not merely circumcised but who also walk in the footsteps of the faith that our father Abraham had before he was circumcised.
12 And it means further that Abraham is father of all people who embrace what God does for them while they are still on the "outs" with God, as yet unidentified as God's, in an "uncircumcised" condition. It is precisely these people in this condition who are called "set right by God and with God"! Abraham is also, of course, father of those who have undergone the religious rite of circumcision not just because of the ritual but because they were willing to live in the risky faith-embrace of God's action for them, the way Abraham lived long before he was marked by circumcision.
New King James Version
12 and the father of circumcision to those who not only are of the circumcision, but who also walk in the steps of the faith which our father Abraham had while still uncircumcised.
New Living Translation
12 And Abraham is also the spiritual father of those who have been circumcised, but only if they have the same kind of faith Abraham had before he was circumcised.
To meet the views of the Jews, the apostle first refers to the example of Abraham, in whom the Jews gloried as their most renowned forefather. However exalted in various respects, he had nothing to boast in the presence of God, being saved by grace, through faith, even as others. Without noticing the years which passed before his call, and the failures at times in his obedience, and even in his faith, it was expressly stated in Scripture that "he believed God, and it was counted to him for righteousness," Genesis 15:6. From this example it is observed, that if any man could work the full measure required by the law, the reward must be reckoned as a debt, which evidently was not the case even of Abraham, seeing faith was reckoned to him for righteousness. When believers are justified by faith, "their faith being counted for righteousness," their faith does not justify them as a part, small or great, of their righteousness; but as the appointed means of uniting them to Him who has chosen as the name whereby he shall be called, "the Lord our Righteousness." Pardoned people are the only blessed people. It clearly appears from the Scripture, that Abraham was justified several years before his circumcision. It is, therefore, plain that this rite was not necessary in order to justification. It was a sign of the original corruption of human nature. And it was such a sign as was also an outward seal, appointed not only to confirm God's promises to him and to his seed, and their obligation to be the Lord's, but likewise to assure him of his being already a real partaker of the righteousness of faith. Thus Abraham was the spiritual forefather of all believers, who walked after the example of his obedient faith. The seal of the Holy Spirit in our sanctification, making us new creatures, is the inward evidence of the righteousness of faith.