What does the Bible say about the need for regeneration?

In John 3:3, Jesus explicitly declares the necessity of being born again by stating, "Except a man be born again, he cannot see the kingdom of God." This underscores the doctrine of regeneration, which teaches that due to the fallen nature of humanity, we cannot understand or accept the things of God without divine intervention. The Apostle Paul elaborates on this in 1 Corinthians 2:14, indicating that the natural man does not receive the things of the Spirit of God because they are spiritually discerned. Therefore, a new birth, or regeneration, is essential for anyone to grasp the gospel and the kingdom of God.