2 Now mark well, beloved, while the Lord suggests and bestows what I may speak, that here is intimated to us no slight mystery. You know the question before us; seek ye out the solution of it. But, to make the solution desirable, let us repeat the theme. The point that troubles us is, why the evangelist said, “For Jesus Himself testified that a prophet has no honor in his own country.” Urged by this, we go back to the preceding words, to discover the evangelist's intention in saying this; and we find him relating, in the preceding words of the narrative, that after two days Jesus departed from Samaria into Galilee.
Was it for this, then, you said, O evangelist, that Jesus testified that a prophet has no honor in his own country, just because He left Samaria after two days, and made haste to come to Galilee? On the contrary, I should have thought it more likely, that if Jesus had no honor in His own country, He should not have hastened to it, and left Samaria. But if I am not mistaken, or rather, because it is true, and I am not mistaken; for the evangelist saw what he was saying better than I can see it, saw the truth better than I do, he who drank it in from the Lord's bosom: for the evangelist is the same John who, among all the disciples, reclined on the Lord's breast, and whom the Lord, owing love to all, yet loved above the rest.
Is it he, then, that should be mistaken, and I right in my opinion? Rather, if I am piously-minded, let me obediently hear what he said, that I may be worthy of thinking as he thought.
Source: Tractates on the Gospel of John (New Advent)