John Chrysostom — as excerpted in the Catena Aurea on John 9:24-34

“(Hom. lviii. 3) Observe then, when he said above, Whether He be a sinner, I know not, it was not that he spoke in doubt; for here he not only acquits him of all sin, but holds him up as one well pleasing to God: But if any man be a worshipper of God, and doeth His will, him He heareth. It is not enough to know God, we must do His will. Then he extols His deed: Since the world began, was it not heard that any man opened the eyes of one that was born blind: as if to say, If ye confess that God heareth not sinners; and this Man has worked a miracle, such an one, as no other man has; it is manifest that the virtue whereby He has wrought it, is more than human: If this Man were not of God, He could do nothing.”