How does circumcision relate to New Testament believers?

The covenant of circumcision given to Abram in Genesis 17 serves as an outward sign of the inward spiritual reality of regeneration. In the New Testament, the concept of circumcision is expanded to mean the circumcision of the heart, achieved through the Holy Spirit (Romans 2:29). This signifies that true belonging to God's people is not based on physical actions but on a spiritual transformation. Jesus emphasized the necessity of being born again (John 3:3), which aligns with the spiritual symbolism of circumcision, thus demonstrating the continuity between the Old and New Testaments in God's redemptive work.