This healing story is placed after that of the Transfiguration. Mark gives a long and graphic account of a healing story narrated by all three evangelists.
Briefly, while Jesus and his three closest disciples were away on the mount of the Transfiguration, the disciples were trying out their hand at an exorcism. Quite unsuccessfully.
The ancient world believed that all ailments came from a demonic force taking possession of one’s body. Health was restored when this evil spirit was forcibly expelled. This is the reason for the large number of exorcisms found in the Gospels, which portray Jesus as the ‘strong man’ who expels his antagonists, the demons, and resumes charge of ‘his property’.
In the story at hand, an epileptic young man keeps foaming at the mouth, and tries to wreak damage upon himself. As the patient’s father describes it, he has “bad fits…keeps falling about, often into the fire, and into the water…”, and the man confesses his utter helplessness.
Jesus rebukes the demon at close distance, and commands the spirit to leave the boy, which it does, leaving the boy almost lifeless. Jesus then restores him to life.
This episode is also the occasion for a teaching on faith. Jesus rebukes the ‘faithlessness’ of this ‘perverse generation’. They want results (a cure, for instance), but are not prepared to trust in him. This provokes the desperate cry of the father of the boy, “Lord, I do believe. Help my unbelief !”, another instance of a prayer of ‘the plain man’.
The disciples are also miffed that they couldn’t work a healing miracle, because as Jesus points out, their faith was too weak. Mark adds Jesus’s caution: some devils are only cast out through prayer. Had the disciples prayed harder, had their faith been stronger – even if it were as tiny as a mustard seed — it would have even moved the adjacent mountain.
This teaching is obviously couched in hyperbole. But it brings home a point: the disciples, like the crowds around, are concerned about the external effect, in this case, a healing. That has sensational and popular value. Jesus however focuses on the internal attitude – putting one’s trust in his person, and clinging to him (Jesus) in spite of appearances. It is inner faith which transforms, not the outer cure.