Romans 2:24-28

For the name of God is blasphemed among the Gentiles through you, as it is written.

For circumcision verily profiteth, if thou keep the law: but if thou be a breaker of the law, thy circumcision is made uncircumcision.

Therefore if the uncircumcision keep the righteousness of the law, shall not his uncircumcision be counted for circumcision?

And shall not uncircumcision which is by nature, if it fulfil the law, judge thee, who by the letter and circumcision dost transgress the law?

For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh: