What does the Bible say about being a true Jew?

According to Romans 2:28-29, a true Jew is not defined by outward appearances or physical ancestry, but by an inward transformation. Paul clarifies that circumcision is of the heart, a spiritual act rather than a physical one, indicating that true acceptance by God comes from a heart changed by the Spirit. This spiritual rebirth is essential for being considered part of God's covenant people, as it aligns with Jesus' teaching that emphasizes faith and reliance on Him for righteousness.