1 Corinthians 7:19
Circumcision is nothing, and uncircumcision is nothing, but the keeping of the commandments of God.
Note 4 at 1Co 7:19: This was a very radical statement in Paul's day (see note 4 at Ro 3:19). All of the unbelieving Jews, as well as many of the Jewish Christians, believed that circumcision was essential for salvation. Paul said that it was "nothing" ("one of no consequence or interest" [American Heritage Dictionary]).