"How can a man be born when he is old? can he enter the second time into his mother's womb, and be born?"

"Verily, verily, I say unto thee, except a man have been born of water and the spirit, he cannot enter into the kingdom of God." (John 3:5)
This verse is in answer to a question. The first word of Jesus to Nicodemus in a word that brings a question. The true teacher seeks to provoke activity of mind and curiosity in the learner. The question is certainly a most absurd one, but Nicodemus had no time to prepare a sensible answer. It is easy for us to be wise over the introductory declaration of Jesus, because we look at it with plenty of illustrations and explanations shining upon it. But Nicodemus, in all his previous thinking, had nothing to make him expect Jesus would speak; and so it is little wonder to find him staggered, confused, utterly bewildered, to hear Jesus speaking thus calmly of such a wondrous  experience. The question, however absurd, leads on to a piece of most practical information.
We are not to suppose that being born over again means to live natural life over again. Few would care for that, traveling over the old road, meeting the old difficulties, fighting the old battles. Jesus explains that to be born again is to be born of water and of Spirit. Being born of water means  passing through the experience  of repentance. The true disciple of John the Baptist was born of water. He repented changed from his old view of life, manifested that changed view by changed habits and practices, and, for sign of all this, he was baptized with water.
Being born of water takes us only a small way into the regeneration. Must follow the discipleship of John with Jesus. You may cease to care for the old, and yet have not found your way to possession of the new. The only creature worth calling  such is the new creature in Christ Jesus. You must feel in your heart the warmth of Him who has eternal life. By repentance, old things pass away; by spiritual birth, all things become new. The spiritual man looks on a virtually new world. The precious becomes worthless, and the worthless precious--the once neglected  is sought for, and the once sought for is neglected.