Romans 2:28-29 Niv

We who worship by the Spirit of God are the ones who are truly circumcised. We rely on what Christ Jesus has done for us. We put no confidence in human effort.
(Philippians 3:3 NLT)

In the New Testament circumcision is regarded as spiritual and inward. Paul
said it quite emphatically, “Neither is that circumcision which is outward in
the flesh... circumcision...

The true Jew is one who belongs to God in heart, a man whose circumcision is not just an outward physical affair but is a God-made sign upon the heart and soul, and results in a life lived not for the approval of man, but for the approval of God. (Romans 2:29 Phillips)

The Cross, as the instrument of spiritual
circumcision, has to be applied to this self-life deeper and ever more...