Augustine of Hippo
Catena Aurea · Johannesevangelium 7
Now about the midst of the feast Jesus went up into the temple, and taught. And the Jews marvelled, saying, How knoweth this man letters, having never learned? Jesus answered them, and said, My doctrine is not mine, but his that sent me. If any man will do his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself. He that speaketh of himself seeketh his own glory: but he that seeketh his glory that sent him, the same is true, and no unrighteousness is in him.
(Tract. xxix. 2) All, it would appear, admired, but all were not converted. Whence then the admiration? Many knew where He was born, and how He had been educated; but had never seen Him learning letters. Yet now they heard Him disputing on the law, and bringing forward its testimonies. No one could do this, who had not read the law; no one could read who had not learnt letters; and this raised their wonder.