Romans 2:29
The real Jew is the man who is a Jew on the inside, and real circumcision is heart-circumcision, a spiritual, not a literal, affair. This man's praise originates, not with men, but with God.
Romans 4:11
Afterward he received the mark of circumcision as God's seal of his right standing with Him on condition of faith which he had before he was circumcised, that he might be the forefather of all who have faith while still uncircumcised, that they might have their faith credited to them as right standing with God;
Colossians 2:11
And through your union with Him you once received, not a hand-performed circumcision but one performed by Christ, in stripping you of your lower nature,