Matthew 17:16

“And I brought him to your disciples, and they could not cure him.”

But then came the body blow. The disciples had been unable to cure the boy. It is noteworthy that we are shortly to learn that they were themselves shocked at their failure. They had expected to be successful, as it would appear up to this point they always had been. They were unable to understand their failure themselves. Thus they had clearly exercised a certain amount of faith, sufficient usually to achieve success. But it had not been enough. Before we are too critical we should note that probably all nine of the remaining Apostles were there and that not one of them had been able to be successful. It would seem that this was a particularly powerful demon.

The failure of the disciples has been a theme of this section. They did not understand about the loaves and the fishes (Matthew 14:16); they were afraid of the ghost at sea (Matthew 14:26); they could not understand why only what came from inside could defile a man (Matthew 15:16); they had wanted Him to send the Canaanite woman away without meeting her deepest need (Matthew 15:23); they failed to be aware of how the crowds could be fed (Matthew 15:33); they became anxious about having no bread in spite of all that they had seen and had been taught (Matthew 16:5); the disciples had failed to recognise in John the Baptist, the coming Elijah (Matthew 17:10). And now they have failed to cast out this demon. It is being made quite clear why they must have Jesus with them when they go out to disciple all nations (Matthew 28:19). Furthermore Peter had lost his faith as he looked at the ferocity of the tempest (Matthew 14:28); had sought to dissuade Jesus from the path of suffering (Matthew 16:22); and had wanted to keep Moses and Elijah on the mountain with Jesus (Matthew 17:4). His moment of insight (Matthew 16:16) was seen as far outweighed by his failure to see. But what a different picture is revealed after Pentecost once the living Christ has possessed them through His Spirit.