John Chrysostom
Catena Aurea · Lukasevangelium 9
And it came to pass, that on the next day, when they were come down from the hill, much people met him. And, behold, a man of the company cried out, saying, Master, I beseech thee, look upon my son: for he is mine only child. And, lo, a spirit taketh him, and he suddenly crieth out; and it teareth him that he foameth again, and bruising him hardly departeth from him. And I besought thy disciples to cast him out; and they could not. And Jesus answering said, O faithless and perverse generation, how long shall I be with you, and suffer you? Bring thy son hither. And as he was yet a coming, the devil threw him down, and tare him. And Jesus rebuked the unclean spirit, and healed the child, and delivered him again to his father. And they were all amazed at the mighty power of God.
(ubi sup.) Hence it seems to me more correct to account the father of the demoniac unbelieving, because he also casts reproach upon the holy Apostles, saying that they could not subdue the evil spirits. But it were better to have sought favour from God by honouring Him, for He has respect to them that fear Him. But he who says that those are weak with respect to their power over evil spirits, who have obtained that power from Christ, calumniates rather the grace than those who are adorned with that grace in whom Christ works. Christ is therefore offended with the accusation of the saints, to whom was entrusted the word of holy preaching. Wherefore the Lord rebukes him and those like-minded with him, saying, O faithless and perverse generation. As if He said, Because of your unbelief the grace has not received its accomplishment.