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?
Ver. 4. How can a man, &c.] He understands no more of the doctrine of regeneration (though he could not but have often read of it in Ezekiel, and elsewhere) than a common cow herd doth the darkest precepts of astronomy,1 Corinthians 2:14. All this is gibberish to him. Water ariseth no higher than the spring whence it came; so the natural man can ascend no higher than nature.