Why is being circumcised in Christ important for Christians?

In Colossians 2:11, Paul explains that believers are 'circumcised with the circumcision made without hands,' referring to a spiritual transformation where the believer's sinful nature is put off through their union with Christ. This circumcision symbolizes our complete separation from the law and sin. It highlights that physical circumcision, as practiced in the Old Testament, has been fulfilled in Christ, and that true believers are those marked by this new birth, or spiritual circumcision, enabling them to live a life freed from the bondage of sin. This understanding is crucial for Christians as it reassures them of their identity and status as members of God's covenant community, with no further additions needed.