What does the Bible say about the need for new birth?

The necessity of new birth is emphasized in John 3:3, where Jesus states, 'Unless one is born again, he cannot see the kingdom of God.' This concept signifies a fundamental transformation that must occur in a person's heart, an operation of the Holy Spirit that results in spiritual awakening and new life. This new birth is essential because the natural man, devoid of this divine intervention, is incapable of truly understanding or appreciating spiritual truths, as outlined in 1 Corinthians 2:14, which highlights that the natural man does not receive the things of the Spirit of God.