Charles Ellicott Commentary John 9:21

"but how he now seeth, we know not; or who opened his eyes, we know not: ask him; he is of age; he shall speak for himself." — John 9:21 (ASV)

But by what means he now sees.—Better, but how he now sees. The answer is in the exact words of the question, which is not seen in our version. They will not go beyond the plain matters of fact of which they were certain.

Or who has opened his eyes.—They move on here to a fourth question, which was not asked, but which they see to be the real point the Pharisees are aiming at, and in which they have determined not to be entangled.

He is of age, ask him.—The better reading here is probably that which places “ask him” first: ask him, he is of age. The Received Text has been influenced by John 9:23. The Greek expresses with the fullest emphasis—an emphasis difficult to preserve in English—that they intend to have nothing to do with this third question, but to leave it to their son to answer. Literally, it is, Ask him; he is of full age; he himself will speak about himself.