What does the phrase 'you must be born again' mean?

The phrase 'you must be born again' originates from Jesus’ conversation with Nicodemus in John 3:3, where He states, 'Except a man be born again, he cannot see the kingdom of God.' This emphasizes the necessity of spiritual rebirth through the Holy Spirit, indicating that one cannot come to faith or understand spiritual truths without this divine work. Being born again signifies the transformation where an individual is given new life, enabling them to trust and believe in Christ as their Savior. Without this transformation, no one can enter into a relationship with God—this is a part of the pure, sovereign grace demonstrated by God.