Search Bible Outlines and commentaries




Grant Osborne: The disciples have a smattering of understanding (17:13) but a real deficiency of faith (17:20a) and need the presence of Jesus more than ever. In fact, the incredible contrast between Jesus’ preincarnate glory (v. 2) and the disciples’ unbelief (v. 17a) shows the sad state of affairs. . .  this becomes a lesson on the danger of unbelief and the power of faith to accomplish great things.

D. A. Carson: The contrast between the glory of the transfiguration and Jesus’ disciples’ tawdry unbelief (see v.17) is part of the mounting tension that magnifies Jesus’ uniqueness as he moves closer to his passion and resurrection.

Warren Wiersbe: We move from the mountain of glory to the valley of need.  The sudden appearance of Jesus and the three disciples startled the multitudes (Mark 9:15).  The distraught father had brought his demonized son to the nine disciples, begging them to deliver him, but they could not.  The scribes had noticed their failure and were using it as a reason for argument.  And while the disciples were defending themselves, and the scribes were accusing them, the demon was all but killing the helpless boy.

When we compare the gospel accounts of this dramatic scene, we discover that this only son was indeed in great trouble and danger.  Matthew recorded that the boy was an epileptic (lunatic), very ill, and suicidal, falling into the fire and the water.  Mark described him as a mute, who often fell to the ground foaming at the mouth and grinding his teeth.  After this display, the boy would go into a kind of rigor mortis.  Dr. Luke said that the boy was an only son and that he would scream as he went into these convulsions.  While some of these symptoms can have natural causes, this boy was at the mercy of a demon. The disciples had been helpless to do anything.  No wonder the father rushed to Jesus’ feet.

Our Lord’s first response was one of sorrow.  As He beheld the embarrassed disciples, the arguing scribes, and the needy father and son, He groaned inwardly and said, “How long shall I be with you and put up with you?” (Luke 9:41 NASB).  Their unbelief and spiritual perversity were a burden to Him.  What must our Lord feel as he looks at powerless believers today?

John Walvoord: The lessons of this incident are obvious.  It is not the greatness of the problem that is the difficulty; it is the lack of faith on the part of believers.  How quickly Jesus responded to the simple and sincere cry of the father of the child, “Lord, I believer; help thou mine unbelief” (Mk 9:24).

Stanley Saunders: Matthew’s portrayal of the disciples in this section of the Gospel is both sobering and hopeful: sobering because of their painful incapacity to discern and fully embrace the power of God, not only at work in Jesus but available to them as well, and hope-filled not because of any innate capacity on the part of the disciples themselves, but because Jesus keeps affirming just how much power is available, even to those with mustard-seed faith. Within this tension we can easily see ourselves.

Stu Weber: True dependence on God’s power will give the kingdom citizen all he or she needs to do the kingdom work successfully.  The failure of the nine disciples, who had remained below at the foot of the mountain, happened as the glory and authority of Jesus was being revealed on the mountain. In spite of the power available to them (17:2-5; also 10:1, 8) and in spite of the truth about Jesus that they had confessed (16:16), their understanding and faith were still limited.

Daniel Doriani: These then are the marks of the faith that moves mountains.

  1. First, it progresses, even if slowly.
  2. Second, it is genuine: it does not trust in past successes or in techniques, but in the Lord himself.
  3. Third, it engages the whole person, mind and emotions.
  4. Fourth, it takes action when it is time to act.
  5. Fifth, it rests in our great God, who can do what seems to be impossible for us when we trust in him.


A power failure is a serious problem.  You are counting on that power to perform a certain task reliably and when that power fails, there can be drastic consequences.  Here we have a failure on the part of the disciples to exercise faith in the healing power of Jesus to meet the desperate need of this man whose son is plagued by a destructive demon.  The disciples could not get the job done.

A.  (:14) Persistence of the Pleader

And when they came to the multitude, a man came up to Him,

falling on his knees before Him, and saying,

William Barclay: We cannot but be moved by the faith of the boy’s father. Even though the disciples had been given power to cast out devils (Matthew 10:1), here was a case in which they had very obviously and publicly failed. And yet in spite of the failure of the disciples, the father never doubted the power of Jesus. It is as if he said: “Only let me get at Jesus himself, and my problems will be solved and my need will be met.”

B.  (:15) Severity of the Suffering

Lord, have mercy on my son, for he is a lunatic, and is very ill;

for he often falls into the fire, and often into the water.

Robert Gundry: The two instances of “often” tell how badly the man’s son suffers.

William Hendriksen: It was the pity or compassion of the Lord to which the tempest-tossed father appealed.  He did not doubt the fact that Jesus was indeed filled with mercy and kindness.  That is why he pleaded, “Lord, take pity on my son.”  On the other hand, the man’s faith in Christ’s power needed strengthening (Mark 9:22-24).

Charles Swindoll: The symptoms were complex:

  • He was mute but able to scream (Mark 9:17; Luke 9:39).
  • He was being slammed to the ground and would become stiff (Mark 9:18; Luke 9:42).
  • He would foam at the mouth and grind his teeth (Mark 9:18, 20; Luke 9:39).
  • He would convulse and roll on the ground (Mark 9:20; Luke 9:39, 42).
  • He was being thrown into fire and water (Matt. 17:15; Mark 9:22).
  • He was being physically injured after each attack (Luke 9:39).

I can’t imagine how much that boy’s family suffered! Somehow, the father had learned that Jesus of Nazareth was in town and that He had a reputation for working miracles.

J. Ligon Duncan: In Mark, chapter 9, verse 25, we’re told that this young man was also unable to speak, and he was unable to hear.  So in addition to being grievously vexed with this malady of epilepsy, he was deaf and dumb, and then, of course, Matthew and Mark make it very clear that this child is demon-possessed.  Three maladies vex this boy.  The exact relation between his demon-possession and the other diseases is not specified.  Was Satan given the power to bring about these physical symptoms, or did Satan take opportunity with these biblical symptoms to afflict this boy?  We are not told in full, but Satan’s hand is in it, the supernatural is in it.  But, also, this child is afflicted physically.

C.  (:16) Failure of the Faith Healers

And I brought him to Your disciples, and they could not cure him.


A.  Frustration of Jesus with His Disciples

And Jesus answered and said, ‘O unbelieving and perverted generation,’

Grant Osborne: It is debated whether the “depraved generation” is mainly the crowds (seen in the second person plurals and in “generation” [γενεά], referring to the continued rejection by the crowds) or the disciples, the nearest antecedent and the focus of this pericope.  However, it is best to see this as a both-and situation, since both groups are in the immediate context.  In their failure, the disciples have joined the rest of the Jewish people in their unbelief and perversity. . .

The two-part rebuke centers first on his continual presence with them (“I will be” [ἔσομαι]) and then on his endurance of them (“I will put up with” [ἀνέξομαι]). Implicit in both is his imminent departure from this earthly sphere. Jesus’ followers do not have long to get their act together! In light of this persistent failure, Jesus takes the matter in his own hands and commands that the boy be brought to him.

Stu Weber: Jesus’ harsh rebuke was directed toward the disciples. It was not surprising to hear him call them unbelieving, for he had already confronted their lack of faith many times. But for Jesus to address the disciples as part of an unbelieving and perverted generation was to lump them together with obstinate Israel and its hypocritical leaders (cf. 11:16; 12:39; 16:4).

R. T. France: The key, as has been so often stated in previous accounts of miracles, lies in faith (8:10, 13, 26; 9:2, 22, 28–29; 14:31; 15:28), but in this case the faith that is missing is not that of the one seeking help but that of the would-be miracle-workers themselves. The sovereign authority of Jesus the Messiah in healing and exorcism is unique; his disciples can draw on it only by faith, and that is what in this case they have failed to do. . .

The frustration Jesus expresses here stands out as unusual in this gospel just as does his exultation in God’s revelation in 11:25–26; the two outbursts express the opposite poles of his paradoxical mission. It has added force at this point in the narrative just as Jesus and the three other disciples are returning from their “mountain-top experience,” and it is possible that the echo of Moses’ complaint reflects the recent meeting with Moses and Elijah, each of whom equally found the people of their day extremely trying (see e.g. Exod 17:4; 1 Kgs 19:10). Jesus has accepted that he will be rejected by the official leadership of Israel (16:21), but to find himself let down even by his own disciples evokes a rare moment of human emotion on the part of the Son of God.  Cf. the “How long?” laments of the psalms (Ps 4:2; 13:1–2 etc.) and prophets (Jer 4:14, 21; 12:4 etc.).

Robert Gundry: Unbelief amounts to a perversion of discipleship. “O” lends gravity to Jesus’ exasperated questions. “How long shall I be with you?” alludes to Jesus as “God with us” (1:23). In 28:20 he’ll answer his own question of how long: “And behold, I am with you all the days till the consummation of the age.” The command to bring the son to Jesus shows Jesus’ determination to expose the baselessness of unbelief.

B.  Lament of Jesus over the Dullness of His Disciples

how long shall I be with you? How long shall I put up with you?

C.  Compassion of Jesus for the Suffering

“Bring him here to Me.


A.  Rebuking the Demon = Successful Spiritual Exorcism

And Jesus rebuked him,

and the demon came out of him,

J. Ligon Duncan: And then, Jesus displays His power.  He demands the demon to leave with a sharp rebuke, and that displays His love and His concern, His compassion in this time of need and malady and sickness and supernatural possession.  But it also displays His power, and we see in this passage the connection between unbelief and perversity.  It is hardened unbelief that has led the scribes to become so perverse as to take delight in seeing ministers not be able to minister to the people that they are attempting to minister unto.  Only perversity can look at this situation and feel that way.  And yet, these religious leaders felt that way. Why?  Because of unbelief.  Hardened unbelief is now keeping them from having normal human compassion.

B.  Restoring the Boy to Full Health = Instant Physical Cure

and the boy was cured at once.

Donald Hagner: This verse is remarkable for its directness and the conciseness of its three main clauses, each with a different subject: ὀ Ἰησοῦς, “Jesus,” τὸ δαιμόνιον, “the demon,” and ὁ παῖς, “the child.”



A.  (:19) Defeated Disciples Look to Jesus for Answers

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

Daniel Doriani: The father viewed Jesus’ disciples as his representatives. In the absence of the master, trained deputies should be able to perform the master’s work. Indeed, in the past Jesus had empowered the disciples to heal disease and cast out demons and they had succeeded (Matt. 10:8; Luke 9:6; 10:17). The father asked the disciples to heal his boy. They tried and failed. The demon who stood behind the disease had resisted.

This failure is puzzling since Jesus had bestowed the power to exorcise demons, and the disciples had already exercised it. A little later, the disciples raised this very issue: “Why couldn’t we drive it out?” (Matt. 17:19). Jesus replied, “Because you have so little faith” (17:20). The disciples’ surprise at their failure suggests that they assumed they could solve this problem. Why? Because they began to trust in themselves, in their gifts, their skills, rather than trusting the Lord. They apparently thought they had the gifts, the training, and the experience to make this work.

R. T. France: Perhaps they had become over-confident in the authority Jesus had given them, so that they assumed they could carry out an exorcism as a matter of course; the added comment in Mark 9:29 that “this kind will not come out except through prayer [and fasting]” implies that they had not prayed for God’s power over the demon. Or perhaps the problem was the opposite, that in the absence of Jesus and the leading disciples up the mountain the remaining disciples did not have the faith to draw on God’s power for themselves, despite Jesus’ authorization, and so their attempt had lacked conviction. At any rate the “little faith” with which Jesus has several times charged his disciples (6:30; 8:26; 14:31; 16:8) has now proved to have serious consequences. For another failed attempt at exorcism see Acts 19:13–17.

William Hendriksen: They had not sufficiently taken to heart the comfort they should have derived from the assurances which their Lord had given them (7:7-10; 10:8), and had not persisted in prayer.  When the demon did not immediately leave they should not have stopped praying. . .  A mustard seed, though at first very small, yet, because of its uninterrupted and vital contact with its nourishing environment, grows and grows until it becomes a tree so tall that the birds of the air come and lodge in its branches.  Accordingly, “faith as a mustard seed” is the kind of trust in God which does not immediately give up in despair when its efforts do not meet with immediate success.  It maintains its uninterrupted and vital contact with God and therefore continues to pray fervently, knowing that God at his own time and in his own way will bestow the blessing.  Such faith links its possessor with the inexhaustible and infinite resources of God’s power, wisdom and love.  It operates in harmony with God’s revelation in his Word.  Consequently, its prayers are not motivated by sinful desires, and it does not tempt God.  It is therefore able to remove mountains.

B.  (:20-21) Lesson of the Mustard Seed: When Faith Is Little, It Must Grow and Persevere to See God Accomplish the Impossible

  1. (:20a)  Their Faith Was Little

And He said to them, ‘Because of the littleness of your faith;’

Grant Osborne: The disciples have frequently been chided for their “little faith” (6:30; 8:26; 14:31; 16:8). In those passages we decided this does not refer to total disbelief but rather to a vacillating, struggling faith. Moreover, “faith” does not simply mean certitude that God will grant the request but rather a total dependence on the God who watches after his children. That is the case here. They likely believed their newfound power over illness and the demonic realm gave them status, and they may have been showing off rather than centering on the God who alone has true power. Such self-centeredness guarantees failure.

Charles Swindoll: Jesus was undoubtedly using hyperbole to drive home His point of the importance and power of faith. He used one of the smallest things in the world —a mustard seed —to condemn the relatively tiny faith of the disciples. If such small faith had the potential to move Mount Hermon —the biggest thing on the horizon —then the disciples’ faith must have been microscopic! Far from comforting, this scolding would have discouraged and shamed the disciples even more.

D. A. Carson: In Mark, Jesus tells them that this case requires prayer—not a form or an approved rite, but an entire life bathed in prayer and its concomitant faith. In Matthew, Jesus tells his disciples that what they need is not giant faith (tiny faith will do) but true faith—faith that, out of a deep, personal trust, expects God to work.

  1. (:20b)  Their Faith Needed to Grow and Persevere as a Mustard Seed

for truly I say to you, if you have faith as a mustard seed,

you shall say to this mountain, ‘Move from here to there,’ and it shall move;

and nothing shall be impossible to you.

Warren Wiersbe: “Faith as a grain of mustard seed” suggests not only size (God will honor even a little faith), but also life and growth.  Faith like a mustard seed is living faith that is nurtured and caused to grow.  Faith must be cultivated so that it grows and does even greater exploits for God (1 Thess. 3:10; 2 Thess. 1:3).  Had the nine disciples been praying, disciplining themselves, and meditating on the Word, they would have been able to cast out the demon and rescue he boy.

Stu Weber: Many people misinterpret the promise, “nothing will be impossible for you,” and similar statements in the New Testament (e.g., John 14:13-14). This is not a blanket coverage of any desire we might express to God in prayer. Biblical faith taps into God’s power and authority, but it can be exercised only in accordance with God’s will (cf. 1 John 5:14). Biblical faith assumes not only a belief in God’s power, but also a heart after God’s own heart, which desires and asks for the things of God—not personal “wants.” This is an important caution in light of the erroneous “name it and claim it” theology we hear so often today.

Leon Morris: He is saying that there are infinite resources open to the believer, and he is calling on those who follow him to exercise the faith they have.

Craig Blomberg: Much is not accomplished for the kingdom because we simply do not believe God will adequately empower us or else because we undertake various activities in our own strength rather than God’s.

Robert Gundry: The great depth of the bases of the mountains made the mountains a natural symbol of stability. In this conceptual framework you could hardly think of a more hyperbolic figure of power than that of moving a mountain. “If you have faith like a grain of mustard” indicates what could be. “It will move away; and nothing will be impossible for you” indicates what would be if the “could” turned into an actuality. “Amen I tell you” adds assurance. And the introductory “For” makes the whole statement an explanation of “Because of the littleness of your faith.”

We tend to gloss over the truth that our God can do the impossible:

  Got any rivers you think are uncrossable?

            Got any mountains you can’t tunnel through?

            God specializes in things thought impossible

            He can do just what no other can do.


He is able to deliver thee,
He is able to deliver thee;
Though by sin oppressed, go to Him for rest;
“Our God is able to deliver thee.”

  1. (:21)  [Verse omitted from best manuscripts]

[“But this kind does not go out except by prayer and fasting.”]

D. A. Carson: [This verse is] omitted by a powerful combination of witnesses. It is obviously an assimilation to the synoptic parallel in Mark 9:29. There is no obvious reason why, if original, it should have been omitted.

R.V.G. Tasker: These last words, which constitute verse 21 in AV, should almost certainly be omitted from the text of Matthew (as in RV and RSV) on the authority of Codex Sinaiticus, Codex Vaticanus, and the ancient Syriac and Egyptian versions.  They would seem to have been imported form Mark ix. 29 in the interest of harmonization.