Church Fathers on Matthew 17:18

Peter, anxious for such desirable life, and preferring his own benefit to that of many, had said, 'It is good for us to be here.' But since charity seeks not her own, Jesus did not this which seemed good to Peter, but descended to the multitude, as it were from the high mount of His divinity, that He might be of use to such as could not ascend because of the weakness of their souls; whence it is said, 'And when he was come to the multitude;' for if He had not gone to the…

is to be noted, that were not man fortified here by Providence, he would long since have perished; for the daemon who cast him into the fire, and into the water, would have killed him outright, had God not restrained him.

In saying, 'And I brought him to thy disciples, and they could not heal him,' he covertly accuses the Apostles, whereas that a cure is impossible is sometimes the effect not of want of power in those that undertake it, but of want of faith in those that are to be healed.