How Is Abraham the Father of Us All?

Is this blessing then upon the circumcised, or upon the uncircumcised also? For we say, "Faith was reckoned to Abraham as righteousness." How then was it reckoned? While he was circumcised, or uncircumcised? Not while circumcised, but while uncircumcised; and he received the sign of circumcision, a seal of the righteousness of the faith which he had while uncircumcised, that he might be the father of all who believe without being circumcised, that righteousness might be reckoned to them, and the father of circumcision to those who not only are of the circumcision, but who also follow in the steps of the faith of our father Abraham which he had while uncircumcised. (Romans 4:9–12)

Paul anticipated the question that Jews would be asking at this point in his argument: “If Abraham was justified by his faith alone, why did God demand circumcision of Abraham and all his descendants?”

Most Jews in New Testament times were thoroughly convinced that circumcision was not only the unique mark that set them apart from all other men as God’s chosen people but was also the means by which they became acceptable to God. . . .

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