What does the Bible say about the necessity of the new birth?

The necessity of the new birth is foundational in scripture, as indicated in John 3:3, where Jesus states that one must be born again to see the kingdom of God. The new birth, or regeneration, is a work of God's grace, enabling individuals to worship God in spirit and in truth (John 4:24). Without it, one's religious activities, such as being a Jew outwardly, are insufficient; the inward transformation is required to truly know and live for God. This new birth is effectually granted by God at the right time and in the right way, revealed to us throughout both the Old and New Testaments.