But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God. Romans 2:29
The verses leading up to that one are all talking about people who judge others, yet commit the same sins they're condemning others for; or those keeping the letter of the law but their hearts still aren't pure.
It also talks about the reverse of that, those who haven't corrected the outside, yet the inside is pure: "Therefore if the uncircumcision keep the righteousness of the law, shall not his uncircumcision be counted for circumcision?" verse 26.
I sit in awe at verses like that sometimes because they speak so deeply of the "riches of his goodness and forbearance and longsuffering" verse 4.
God is deeply concerned with our hearts.
How concerned are you?