Matthew 17:14-21


Yves I-Bing Cheng, M.D., M.A.




The Lord Jesus often had to bear with unbelief among His own disciples. The story of the healing of an epileptic boy is one example among many. Let’s read this passage. It contains a wonderful lesson on faith and power. Matthew 17:14-21.


Matthew 17:14. And when they had come to the multitude, a man came to Him, kneeling down to Him and saying,

15 "Lord, have mercy on my son, for he is an epileptic and suffers severely; for he often falls into the fire and often into the water.

16 "So I brought him to Your disciples, but they could not cure him."

17 Then Jesus answered and said, "O faithless and perverse generation, how long shall I be with you? How long shall I bear with you? Bring him here to Me."

18 And Jesus rebuked the demon, and it came out of him; and the child was cured from that very hour.

19 Then the disciples came to Jesus privately and said, "Why could we not cast it out?"

20 So Jesus said to them, "Because of your unbelief; for assuredly, I say to you, 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.

21 "However, this kind does not go out except by prayer and fasting."


Powerless disciples


This incident happened on the day after the transfiguration. Jesus and three disciples (Peter, James and John) had gone up to the mount of transfiguration and now, they were coming down to rejoin the others.


As a crowd met Jesus, a man cried out to Him, requesting that the Lord take a look at his son. He explained that his child is an epileptic and suffers severely … he often falls into the fire and often into the water (v. 15). The description of the illness is more detailed in the other gospels. Mark speaks of foaming mouth, grinding teeth, rigid body and not being able to speak (Mark 9:17-18). Luke mentions his crying out, convulsions, bruises and foaming mouth (Luke 9:39). These symptoms lead most to see epilepsy as present, or at least a type of disorder that looks like epilepsy. But it was not just a physical problem. Epilepsy itself does not cause suicidal tendencies. The boy’s illness was also a spiritual one. He was demon possessed. He had an evil spirit that tried to kill him by causing him to fall into the fire and into the water (Mark 9:22).


Something else compounded the son’s tragic situation: previous effort to cast out the spirit had failed. Having heard of Jesus to be a successful exorcist, the father had come to Jesus, hoping for a cure for his son. But Jesus was nowhere to be found. He then went to the disciples. This was an appropriate decision since the disciples had been entrusted with a certain measure of power to cast out demons. We read in Matthew 10:1 that when He had called His twelve disciples to Him, He gave them power over unclean spirits, to cast them out, and to heal all kinds of sickness and all kinds of disease. In this particular case, they could not drive out the demon. No doubt they tried their very best, but it did not work.


Then came Jesus, and the boy was healed.


This account is not really a healing story as much as it is a story instructing disciples in ability, in power. If you look at this passage carefully, you can see that the word ‘unable’ is a key word. It is used three times:


(-) Firstly, in v. 16. They could not (ouk edynethesan) cure him.

(-) Secondly, in v. 19. Why could we not (ouk edynethemen) cast it out?

(-) And thirdly, in v. 20. Nothing will be impossible (ouden adynatesei) for you.


The root of the ‘unable’ word in these three places (edynethesan, edynethemen, adynatesei) is dunamis, which means ‘power’. This story, then, is a story that has to do with power.


We find a contrast between Jesus’ power to heal and the disciples’ impotence. But the miraculous healing itself takes second place. Jesus’ exorcism is described with minimal detail in a single verse (v. 18). All the emphasis falls on the disciples’ inability to heal the boy, on their lack of power, and what this reveals about their spiritual condition.


Faithless people


The failure of the disciples drew out from Jesus a surprising response. I would like you to notice particularly the tone of His words. O faithless and perverse generation, how long shall I be with you? We can sense His frustration and exasperation. He rebuked the audience by calling them a faithless and perverse generation.


To whom was Christ speaking? Who was being rebuked?


The reference to a perverse generation has OT roots. It is applied to the Israelites in the song of Moses in Deuteronomy 32. Moses said to them that they were a perverse and unbelieving generation. They saw the works of God, and still did not believe. Therefore God was deeply disappointed with them.


Deuteronomy 32.4. The Rock, his work is perfect; for all his ways are justice. A God of faithfulness and without iniquity, just and right is he. (Notice the words ‘faithfulness and without iniquity,’ the exact opposite of faithless and perverse.)

5 They have dealt corruptly with him, they are no longer his children because of their blemish; they are a perverse and crooked generation.


Deuteronomy 32.20. And he said, I will hide my face from them, I will see what their end will be, for they are a perverse generation, children in whom is no faithfulness.


‘A perverse and crooked generation, children in whom there is no faithfulness.’ These were the Israelites in the time of Moses. They were God’s children. But they were no longer His children insofar as they were faithless and perverse. And in Matthew 17:17, we find the same words which were applied to Israel of Jesus’ day. Jesus rebuked the Jewish people as a whole.


But His words were also intended for the disciples. O faithless and perverse generation. Jesus included them among the faithless. We can see that from His answer to the disciples when they asked, ‘Why couldn’t we cast him out?’ He said, Because of your unbelief (v. 20). Because you lack faith. This was Jesus’ deepest source of His complaint. At a superficial level, the disciples did have some faith. They thought they would be able to exorcise the demon since they had been successful in the past in this kind of work. Now they are surprised by their failure. Though they had faith, yet their faith was poor and ineffectual. It produced the same effect as no faith. In that sense, it may be said that they were faithless.


The need for power


O faithless and perverse generation, how long shall I be with you? Another thing that stands out from these words is that the Lord expected the disciples to be able to deal with the case. There is no point rebuking the disciples if they were not expected to do it in the first place. They should have been able to heal the boy. But they could not. There was nothing more frustrating to Jesus, I am sure, than having taught His disciples all this time, He saw that they were still spiritually weak. They were now coming to the end of their period of training, Jesus was about to be offered up for the sins of the world, and they still lacked faith.


Notice those words. How long shall I be with you? The point of the statement is this. ‘You are depending on Me to do these things, to break the power of the evil one, to cast out this demon. What will happen when I will not be here anymore? I am about to depart, to go the cross. Soon I will not be with you. How are you going to work for the salvation of the world? How are you going to deliver mankind from the power of evil and the power of sin? What you need is power. You have to know how to handle spiritual power.’


It is Paul who wrote, For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places (Ephesians 6:12). In order to deal with this kind of power, you need to have power yourself, the power to wrestle against sin, against the world, against Satan, against the flesh.


But remember this. The fact that you are a follower of Christ does not automatically mean that you are equipped with spiritual power. Just like the apostles, you have to learn to appropriate the power that you have in God.


The path to power


How then do we get power? How do we draw on God’s power? The disciples had been given and promised unusual power earlier, and they had ministered effectively (Matthew 10:1; Luke 10:17). But now the power seemed to be gone, and they were unable to minister. ‘Why?’ they asked (Matthew 17:19). Jesus’ diagnosis of the source of the disciples’ powerlessness is extremely simple. ‘It is because you don’t really believe.’ In other words, the authority to throw out demons or to do any kind of spiritual work is not enough on its own. Faith is necessary. And the failure of the disciples was due to their failure to appropriate God’s power by faith.


But what does faith mean? Faith, in the context of Matthew 17:20, means self-emptiness and self-denial. This is the condition that is required for God’s life-giving energy to operate in us. Expressed in a different way, we can say that the path to power is the path of the cross. This principle of power is very important. The path to power is the path of the cross. If your life is going to have any kind of power, you will have to walk on the path of the cross.


Let’s look at the basis of this principle from the context of this passage. We saw in Matthew 16:21 that Jesus told His disciples that He would die. It was quite a shock for them to hear that. Jesus, to die? They thought that He was bringing in the kingdom. They did not realize that it was actually through His death that He would bring in the kingdom of heaven.


Then, immediately after revealing that he was walking towards the cross, He asked the disciples to take up their cross and follow Him. There Jesus preached on the cross by showing that the way that leads to life goes through a narrow road and a narrow gate. If any man would follow Him, he must be prepared to suffer and lose everything in the process, including his own life.


And then, we studied the last verse of Matthew 16 where Jesus said, ‘There are some people who will not taste death before they see the Son of Man coming in His kingdom.’ We saw that it applied to the promise of a spiritual life, of an eternal life, to those who take up their cross.


In the next verse, Matthew 17:1, we have the story of the transfiguration where the heavenly Father glorified the Son. It is important to observe the passive tense. Jesus was transfigured before them. He did not transfigure Himself. He did not just decide that He was going to display His glory for the sake of impressing His disciples. I do not seek My own glory, Jesus said in John 8:50. It was God who transfigured Him. God caused His glory to come upon Jesus in such a way that He was transfigured. Who are the people that the Father glorifies? The people who do not seek their glory, who are prepared to deny themselves and take up the cross.


Notice now the connection between this being glorified by God and Jesus’ approach to death on the cross. What was Jesus doing before the transfiguration? He was praying. Luke 9:29: As He prayed, the appearance of His face was altered, and His robe became white and glistening. What was in His mind when He was praying? His death on the cross. Luke 9:30-31: And behold, two men were talking with Him; and they were Moses and Elijah, who, appearing in glory, were speaking of His departure which He was about to accomplish at Jerusalem. ‘His departure’ means His death. Jesus’ prayer was focused on His sacrifice, His impending death on the cross. This was the goal towards which His whole life was set. As He was praying, as His thought was directed towards His death, there appeared Moses and Elijah to discuss this very subject with Him. He was to go to the cross in Jerusalem in order to become a sacrifice for the sins of mankind.


It was in this context that the Lord Jesus, in the mount of transfiguration, was clothed with God’s glory. And glory, in the Bible, goes together with power. You do not have any kind of radiance, any kind of glory, without power. A Christian who has the power of God is someone who manifests the glory of God. But this does not happen without the humility to take up the cross. That is why I said that the path to power is the path of the cross.


The path of love


Now, what do we mean by the path of the cross? Here is another principle to remember. The path of the cross is the path of self-giving love. When Jesus calls us to take up the cross, He is calling us to a life of self-giving love. Because to take up the cross inevitably means that you no longer live for yourself. Jesus went to the cross, not to save Himself, but to save others. And we are to approach the cross with that same spirit.


The path to power is the path of the cross. And the path to the cross is the path of love. Paul wrote in 1Corinthians 13:2 that I can have a faith that can move mountains, but if I have no love, I am nothing. Anything that I do would be in vain as far as the kingdom of God is concerned. My life would carry no power in the kingdom.


This verse about faith and moving mountains is quite interesting for our lesson because Paul seems to be referring directly to the words of Jesus in Matthew 17:20. Let’s get the context. We will read from v. 28, 1Corinthians 12:28ff. Paul speaks about various gifts of power.


1Corinthians 12:28. And God has appointed these in the church: first apostles, second prophets, third teachers, after that miracles, then gifts of healings, helps, administrations, varieties of tongues.

29 Are all apostles? (do all exercise apostolic authority?) Are all prophets? (do all speak the word of God with power?) Are all teachers? (are you able to expound the word of God with clarity) Are all workers of miracles? (do you have the power to work miracles?)

30 Do all have gifts of healings? Do all speak with tongues? Do all interpret?

31 But earnestly desire the best gifts. (yes, you should desire these gifts of power. Now listen to the last sentence of this chapter)  And yet I show you a more excellent way.


The way to what? The way in which these gifts of power are to function. That is where 1Corinthians 13 comes in. What is the way? It is the way of love. Paul was saying to the Corinthians that the way they were going was destructive to the church as a community. The way they were being called to (and that applies to us too) was one that seeks the good of others before oneself. It is the way of seeking the common good. Exercise these gifts of power in a loving manner so that others will be edified. You see that cross, power, and love cannot be separated.