John 3:3-5
Jesus answered and said to him, “Most assuredly, I say to you, unless one is born again, he cannot see the kingdom of God.” 4 Nicodemus said to Him, “How can a man be born when he is old? Can he enter a second time into his mother’s womb and be born?” 5 Jesus answered, “Most assuredly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God.