Charles Spurgeon Commentary Romans 2:25

"For circumcision indeed profiteth, if thou be a doer of the law: but if thou be a transgressor of the law, thy circumcision is become uncircumcision." — Romans 2:25 (ASV)

Paul is dealing with the Jew, who was inclined to think that he must have an advantage over the Gentiles on account of his circumcision.