Don't marvel that I said to you, 'You must be born anew.'
They are therefore excessively stupid who, having been warned by the common order of nature, do not rise higher, so as to acknowledge that the hand of God is far more powerful in the spiritual kingdom of Christ. When Christ says to Nicodemus that he ought not to wonder, we must not understand it in such a manner as if he intended that we should despise a work of God, which is so illustrious, and which is worthy of the highest admiration; but he means that we ought not to wonder with that kind of admiration which hinders our faith. For many reject as fabulous what they think too lofty and difficult. In a word, let us not doubt that by the Spirit of God we are formed again and made new men, though his manner of doing this be concealed from us. 