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. xxviii. s. 8.) The feast seems, as far as we can judge, to have lasted several days. And therefore it is said, “about the middle of the feast day:c” i. e. when as many days of that feast had passed, as were to come. So that His assertion, I go not up yet to this feast day, (i. e. to the first or second day, as you would wish me,) was strictly fulfilled. For He went up afterwards, about the middle of the feast.