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?"

 When Nicodemus came to Jesus, he said that no one could help being impressed with the signs and wonders that he did. Jesus' answer was that it was not the signs and the wonders that were really important; the important thing was such a change in a man's inner life that it could only be described as a new birth. 