John Chrysostom
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.
(Hom. xxiv. 2) Thou callest Him Rabbi, and sayest that He comes from God, and yet receivest not His sayings, but usest to thy master a word which brings in endless confusion; for that how, is the enquiry of a man who has no strong belief; and many who have so enquired, have fallen from the faith; some asking, how God became incarnate? others, how He was bornb? Nicodemus here asks from anxiety. But observe when a man trusts spiritual things to reasonings of his own, how ridiculously he talks.