In what sense is this true?
The apostle Paul, who made the above claim in Philippians 3:3, knew that circumcision was given as a sign of the covenant between Abraham, his descendants and God. Every male’s foreskin had to come under the knife and that part of the flesh be discarded. It was a gender thing, only a minor operation, but it came to be a source of great pride in Israel and being uncircumcised a contemptuous way of describing God’s enemies and theirs.