29 But a Jew is one inwardly, and circumcision is a matter of the heart, by the Spirit, not by the letter. ~ Romans 2:29
Our hearts are changed by the Holy Spirit. The law, which is a foreshadowing of Jesus taking away the sins of the world, is written on our hearts. Our hearts are circumcised by this because circumcision was the sign of the covenant. The importance of this is that we are now under a new covenant and better covenant that doesn’t just put off our sin for another year, it completely washes us clean, and our sins are blotted out.
In other words, we get a new fresh start with Christ. Our old man is dead, and we are, in fact, a new creation in Christ Jesus. We don’t have to hold on to our past; it is erased. Blotted out. Thrown into the Sea of Forgetfulness. It is no more. We can start over in Christ Jesus. All we have to do is repent and confess that Jesus Christ is LORD.
Peace. Love. Go Forth and Become a New Man.