Romans 2:25

Circumcision does indeed profit, if you obey the Law; but if you are a Law-breaker, the fact that you have been circumcised counts for nothing.

Acts 7:51

"O stiff-necked men, uncircumcised in heart and ears, you also are continually at strife with the Holy Spirit--just as your forefathers were.

Romans 2:23

You who make your boast in the Law, do you offend against its commands and so dishonour God?

Romans 2:28-2

For the true Jew is not the man who is simply a Jew outwardly, and true circumcision is not that which is outward and bodily.

Romans 4:11-12

Before, not after. And he received circumcision as a sign, a mark attesting the reality of the faith-righteousness which was his while still uncircumcised, that he might be the forefather of all those who believe even though they are uncircumcised--in order that this righteousness might be placed to their credit;

Galatians 5:3-6

I once more protest to every man who receives circumcision that he is under obligation to obey the whole Law of Moses.

Galatians 6:15

For neither circumcision nor uncircumcision is of any importance; but only a renewed nature.

Ephesians 2:11-12

Therefore, do not forget that formerly you were Gentiles as to your bodily condition. You were called the Uncircumcision by those who style themselves the Circumcised--their circumcision being one which the knife has effected.

Treasury of Scripture Knowledge

Summary

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

Bible References

But if

Romans 2:23
You who make your boast in the Law, do you offend against its commands and so dishonour God?
Acts 7:51
"O stiff-necked men, uncircumcised in heart and ears, you also are continually at strife with the Holy Spirit--just as your forefathers were.