In Matthew 17:14-21, Mark 9:17-29 and Luke 9:38-43, the Almighty Author chose to have three writers record this miracle and the accounts are rich with principles. The Matthew narrative refers to the boy as an epileptic, the cause being spiritual. All three Gospels agree that the boy was suffering from the influence of evil or demon spirits.
In Matthew, the father of the boy came to Jesus and described how his son would have seizures and fall into fire or into water. Mark’s account adds that the spirit “seizes him, it throws him down; he foams at the mouth, gnashes his teeth, and becomes rigid.” Luke adds, “…a spirit seizes him, and he suddenly cries out; it convulses him so that he foams at the mouth; and it departs from him with great difficulty, bruising him.” The New Living Translation offers this rendering of Luke 9:39: “An evil spirit keeps seizing him, making him scream. It throws him into convulsions so that he foams at the mouth. It batters him and hardly ever leaves him alone.” The father told Jesus, “I spoke to Your disciples, that they should cast it out, but they could not.”
Jesus’ response at this point is somewhat out of the ordinary. Matthew 17:17, Mark 9:19 and Luke 9:41 coincide. The Message handles these verses in this way: Jesus said, “What a generation! No sense of God! No focus to your lives! How many times do I have to go over these things? How much longer do I have to put up with this? Bring your son here.” Matthew and Luke both sum up in a few words what Jesus did next. He rebuked the spirit, it came out, and the boy was healed.
Mark 9:20-27, however, provides the most detail. The child was brought to Jesus and when he, the spirit, saw Jesus, “immediately the spirit convulsed him, and he fell on the ground and wallowed, foaming at the mouth.” Jesus then asked the father how long this had been occurring. The man told Jesus it had been happening since the boy’s infancy, then said to Jesus, “But if You can do anything, have compassion on us and help us.” Jesus then took the man’s “if” and directed the responsibility for believing squarely on the father’s shoulders. “If you can believe, all things are possible to him who believes.” Immediately the father of the child cried out and said with tears, “Lord, I believe; help my unbelief!”
Jesus rebuked the unclean spirit, saying to it, “Deaf and dumb spirit, I command you, come out of him and enter him no more!” The spirit screamed, the child convulsed, but the spirit came out of him. The boy was motionless and looked dead, so that the people present said, “He is dead.” Jesus took him by the hand and lifted him to his feet.
This miraculous incident closes with the disciples coming to Jesus privately and asking Him, “Why could we not cast it out?” Jesus taught them truthfully, but not disdainfully. He told them it was because of their unbelief. The word translated unbelief in the Greek means “little faith” or “littleness of faith.” They were by no means unbelievers, but had experienced great success as recorded in Matthew 10 when they went out healing all kinds of sicknesses and diseases, and casting out spirits. In Matthew 19:21, Jesus said, “However, this kind does not go out except by prayer and fasting.” Mark 9:29 is the comparable verse. Many Greek manuscripts omit the entire verse from Matthew, and the word “fasting” from Mark 9:29. Nevertheless, Jesus taught that there are different kinds of spirits that vary in strength and wickedness (Matthew 12:45; Luke 11:26), and that a disciplined prayer life is crucial in destroying the works of the devil.
This situation had stumped them perhaps because it was new and different, but primarily because the father’s own unbelief was working against them. Jesus went on to encourage them, “If you have faith as a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you.” In essence, He was teaching them that a little genuine faith is all it takes. It is not a matter of more faith, but enough to focus solely on God Who has the power to perform whatever needs to be done.