John 7:15

"How knoweth this man letters, having never learned?" Observest thou how the Evangelist showeth here also their marveling to be full of wickedness? for he saith not, that they admired the teaching, or that they received the words, but simply that they "marveled." That is, were thrown into a state of astonishment, and doubted, saying, "Whence hath this man these things"? when they ought from this very difficulty to have known that there was nothing merely human in Him. But because they would not confess this, but stopped at wondering only, hear what He saith.

But as He taught, "the Jews marvelled;" all indeed, so far as I think, marvelled, but all were not converted. And why this wondering? Because all knew where He was born, where He had been brought up; they had never seen Him learning letters, but they heard Him disputing about the law, bringing forward testimonies of the law, which none could bring forward unless he had read, and none could read unless he had learned letters: and therefore they marvelled. But their marvelling was made an occasion to the Master of insinuating the truth more deeply into their minds. By reason, indeed of their wondering and words, the Lord said something profound, and worthy of being more diligently looked into and discussed. On account of which I would urge you, my beloved, to earnestness, not only in hearing for yourselves, but also in praying for us.

(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.