Matthew 17:20 is Jesus’ answer to a painful question His disciples asked after a failure. They had tried to cast out a demon and could not. Later, away from the crowds, they came to Jesus and asked, “Why couldn’t we do it?”
“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.’”
Jesus does not flatter them. He names the real issue: unbelief. But He does something wonderfully surprising. He does not tell them they need a huge faith. He tells them they need a living faith, even if it is as small as a mustard seed.
A mustard seed in their world was proverbially tiny—one of the smallest of garden seeds. Jesus chooses that image on purpose. He is not glorifying spiritual heroics. He is saying that what matters most is where your faith is placed, not how impressive it looks.
- Little faith in a great Savior is more powerful than great confidence in yourself.
- Weak, trembling trust in Christ is stronger than bold self-reliance.
When Jesus speaks of “this mountain” moving, He is using language that would have sounded impossible to His hearers. Mountains do not simply rearrange themselves. Yet He is not encouraging reckless presumption or a life spent commanding physical mountains. He is painting a picture:
Wherever the will of God and the word of Christ are trusted, obstacles that look immovable bow to His authority.
The disciples had tried to confront evil in their own strength, perhaps leaning on past success or formula instead of present dependence on Him. Jesus answers by calling them back to simple, direct, mustard-seed trust in Him:
- Not faith in faith itself.
- Not faith in technique.
- Faith in Jesus—who He is, what He has promised, and what He is able to do.
Matthew 17:20 does not turn God into a servant of our desires. It turns fearful disciples back into children who trust their Lord. Mountains move not because we finally become powerful, but because He is. Even a seed-sized dependence on Him is enough to pull His power into our weakness.
There is both correction and comfort here:
- Correction, because Jesus takes unbelief seriously.
- Comfort, because He does not demand a flawless, massive faith—only a real one that looks to Him.
For every believer who looks at a situation and whispers, “My faith feels so small,” this verse answers: Bring that small faith to a great Christ. It is not the size that moves the mountain—it is the Savior who does. 🌿
The Verse Inside the Story of Redemption
Matthew 17:20 sits inside a long story where God calls His people to trust Him in the face of impossible odds. From the beginning, God has been the One who moves what cannot be moved when His people take Him at His word.
- Abraham believed the promise of a son when his body was as good as dead, and God counted it to him as righteousness.
- Israel stood trapped between the Red Sea and Pharaoh’s army until God split what could not be split and led them through.
- David faced Goliath not with superior weapons, but with confidence in the Name of the LORD.
In each case, the “mountain” was not removed by human skill alone. It was moved as people leaned—sometimes tremblingly—on what God had said.
That pattern deepens as the story moves toward Jesus. The prophets speak of a coming Servant, a righteous King, a new covenant where God will give His people a new heart and write His law within them. Every promise presses toward Christ.
Matthew 17:20 comes right after Jesus has been transfigured on the mountain (Matthew 17:1–8). Peter, James, and John saw Him in glory, shining with the radiance of His divine nature, with Moses and Elijah appearing beside Him. The Father’s voice declared:
“This is My beloved Son, in whom I am well pleased. Hear Him!”
From that mountain of glory, Jesus comes down to meet a broken scene: a tormented boy, a desperate father, and disciples who could not help. Between His glory and their need stands one issue: unbelief.
When Jesus speaks of mustard-seed faith and moving mountains, He is not handing out a detached principle. He is drawing a straight line between:
- The glorious Son the Father has just affirmed, and
- The real-time trust His followers are called to place in Him.
The “mountain” in the immediate context is a demon that will not yield, a kind of evil the disciples cannot dislodge. Jesus will add in the surrounding verses that this kind “does not go out except by prayer,” highlighting dependence on God, not on technique.
In the larger story of redemption, Matthew 17:20 points us ahead to the greatest “mountain-moving” act of all:
- At the cross, Jesus bears sin, breaks the power of death, and defeats the accusations of the enemy.
- At the empty tomb, He rises and declares that all authority in Heaven and on earth has been given to Him.
From that point on, faith is not a vague spiritual force. It is a response to a finished work and a living Person. The One who tells you that mustard-seed faith can move mountains is the same One who has already moved the mountain of judgment out of the way for those who belong to Him.
The New Testament keeps echoing this:
- We walk by faith, not by sight.
- Faith is the assurance of things hoped for and the conviction of things not seen.
- The life you now live in the body, you live by faith in the Son of God, who loved you and gave Himself for you.
So Matthew 17:20 is not an isolated motivational phrase. It is the voice of the crucified and risen Christ calling His people into the very life He purchased for them—a life where obstacles are real, opposition is real, weakness is real, but His power and faithfulness are more real.
By tying “nothing will be impossible for you” to mustard-seed faith, Jesus is not promising that every wish will be granted. He is telling His followers that no barrier can finally stop what God has purposed to do through those who trust Him. The God who raised Jesus from the dead is not limited by what looks immovable in front of you.
The Verse in the Life of the Believer
For most believers, the problem is not that we never believe—it is that our faith feels small, inconsistent, mixed with fear and doubt. Matthew 17:20 speaks right into that experience.
Jesus does not say, “When your faith feels flawless, then mountains will move.” He says, “If you have faith as a mustard seed…”
That invites you to come to Him exactly as you are:
- With the little courage you have.
- With the tangled questions you cannot yet untie.
- With prayers that sound more like, “Lord, I believe; help my unbelief.”
Mustard-seed faith is still faith. It looks like:
- Choosing to pray again when you feel like nothing is changing.
- Obeying in a small, specific way when you cannot see the whole path.
- Confessing sin and leaning on Christ’s forgiveness instead of hiding.
- Speaking about Jesus to someone even when your voice trembles.
You may not feel powerful in any of those moments. But Matthew 17:20 says that when those small acts grow out of trust in Christ, He is at work—and mountains can move in ways you do not yet see.
Different believers face different “mountains”:
- A long-standing pattern of sin that feels unbreakable.
- A relationship so wounded it seems beyond repair.
- A calling that looks far too big for your limitations.
- A constant undercurrent of fear or shame that will not go away.
Matthew 17:20 does not make light of these. It does not tell you to pretend they are small. It tells you that Jesus is not limited by them, and that even mustard-seed trust in Him can begin to shift what feels immovable.
It is important to say what this verse does not mean:
- It does not mean that if a situation does not change the way you hoped, you must not have had “enough” faith.
- It does not mean you can command anything you want and bind God to your timetable.
God is still God. He is wise, sovereign, and loving. Sometimes He moves the mountain outside you. Sometimes He strengthens you to walk up it, or gives you peace in front of it, or reveals that the real mountain was in your heart. But in every case, the call is the same:
Bring your small faith to a great Savior—keep it turned toward Him.
As you do, you may begin to notice quiet changes:
- Old fears do not grip you as tightly, even if they still whisper.
- Old sins start losing their power as you lean on His Spirit, not just your resolve.
- Old wounds begin to heal as you entrust them to His care, again and again.
Over time, mustard-seed faith grows. Seeds do not stay seeds. In another place, Jesus says the mustard seed becomes a tree where birds can rest. Faith, watered by the Word of God and the work of the Spirit, matures into a steadier, deeper trust.
The enemy wants you to stare at your faith and conclude it is too small. Matthew 17:20 invites you instead to stare at Christ. The question is not, “Is my faith impressive?” but, “Is my Savior faithful?”
He is.
- He has already moved the mountain of condemnation by His blood.
- He has already broken the power of death by His resurrection.
- He has promised never to leave you or forsake you.
So when you stand before what looks impossible, you are not being asked to generate spiritual heroics. You are being invited to take the little trust you have and plant it again in the soil of His promises.
You may say through tears, “Lord Jesus, this feels too big. But You have said that even mustard-seed faith in You is not wasted. I bring You what I have. Help me trust You here.”
He does not despise that prayer. He meets it. And in ways seen and unseen, now or later, mountains move under His hand.
Resting in the Savior Who Honors Mustard-Seed Faith and Still Moves Mountains
Keep Exploring God’s Word on This Theme
If this verse spoke to you, these related passages will help you keep going deeper into who Christ is and what it means to trust Him.
When you need encouragement to keep trusting and resting in the LORD:
Read alongside its surrounding context, Matthew 17:20 keeps doctrine and daily discipleship together. It does not leave the believer with a detached idea, but with truth that steadies faith, corrects false confidence, and points the heart back to Christ. That is why it helps to keep reading this verse in conversation with nearby studies in the same series.
Read Next in Connected Verses
This study belongs inside a wider conversation in Matthew. Follow these nearby passages and connected studies to keep the context, doctrine, and application tied together.
Matthew 17:20 Meaning — Faith Like a Mustard Seed That Moves Mountains
This nearby verse in the same chapter sharpens the immediate context and movement of thought.
Matthew 6:33 Meaning — Seek First the Kingdom of God and His Righteousness
This related study elsewhere in Matthew helps carry the book’s wider themes and message forward.
Matthew 11:29 Meaning — Take My Yoke and Find Rest for Your Soul
This related study elsewhere in Matthew helps carry the book’s wider themes and message forward.
Matthew 11:28 Meaning — “Come to Me, All Who Are Weary”
This related study elsewhere in Matthew helps carry the book’s wider themes and message forward.
Books by Drew Higgins
Leave a Reply