Bede the Venerable
Catena Aurea · Johannesevangelium 3
Nicodemus saith unto him, How can a man be born when he is old? can he enter the second time into his mother’s womb, and be born? Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God. That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Marvel not that I said unto thee, Ye must be born again. The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, and whither it goeth; so is every one that is born of the Spirit.
(in loc.) The question put thus sounds as if a boy might enter a second time into his mother’s womb and be born. But Nicodemus, we must remember, was an old man, and took his instance from himself; as ifhe said, I am an old man, and seek my salvation; how can I enter again into my mother’s womb, and be born?