“Mountains and Mulberry Trees”
Original sermon given on Sunday, October 5, 2025 written and delivered by Pastor Jeff Leininger at First Saint Paul’s Lutheran Church.
Watch the sermon live.
“Mountains & Mulberry Trees”—Luke 17.1-10
In the name of the Living God and the risen Christ. Amen.
Mountains and Mulberry Trees. The Mountain: solid, massive, overwhelming. Nothing more permanent could be imagined in the ancient world, other than the earth itself. It is immovable by its sheer size and mass. The Mulberry Tree: its roots are a tangled web spreading underground three times the size of the tree itself. Just when you think you’ve exhausted yourself pulling up one root, another will be found secured even deeper into the ground. It is intractable not for its sheer mass, but because of the complex root system hidden deep in the ground. The rabbis at the time of Jesus remarked that the mulberry tree’s roots would last 600 years.
Mountains and Mulberry Trees. Jesus uses both in the gospels to illustrate something seemingly spiritually impossible, yet which is overcome by the smallest and most powerful of things: faith… faith but the size of a mustard seed. The mustard seed: so small that if I held it up here you couldn’t even see it. Yet faith this small can move mountains and transfer trees.
The mountain: in Matthew 17 (not Luke 17), the apostles are coming down from the mountain- top experience of the Transfiguration. They’ve seen the full divinity of Christ shinning in all his glory; hung out with Elijah and Moses. But when they come down from the mountain top things start to go awry. A poor boy is oppressed cruelly by a demon, but they can’t manage to drive the evil out. Jesus severely rebukes them and laments their lack of faith, saying, “If you have faith even as small as a mustard seed you can say to this mountain, ‘Get moving’ and it will.”
The proverbial saying of the minute mustard seed appears again here, in Luke 17. Jesus, in today’s gospel, delivers a couple of what I call “spiritual gut punches”. The first: causing “one of these little ones” to sin, to stumble, wins you a millstone with a neck-size hole in it, sinking you to the bottom of the sea. And, just in case you think this gut punch doesn’t apply to you, by “one of these little ones” Jesus isn’t only talking about leading children astray. The phrase likely refers to any of your fellow “little ones” in the faith. So, he rebukes causing any fellow believer to sin or to stumble.
Spiritual gut punch #2: You must forgive. Seven times a day. And this is not meant to be the 1st Century version of the coach’s clicker — “Right. That’s seven. That it. We’re done with forgiveness now.” No, Jesus means that the whole of the Christian life is a life lived in graciousness to others. Seventy times seven.
One preacher described these two spiritual gut punches in this way: “Christians should strive to live lives giving no offense and taking no offence.”[1] (How many problems would we solve in this world if we all lived out this rule!)
It is no wonder then that after spiritual gut punch #1 and #2, the Apostles exclaim, “Lord, increase our faith!” Jesus again reminds them that even faith the size of the mustard seed can extract the 600-year-old Mulberry Tree, roots and all, and sink it into the sea.
Mountains and Mulberry Trees. I think we’ve all got them — and if not yet, one day, sooner or later they will come. The mountain from Matthew 17 is the huge crisis, or the earth-shattering tragedy, or the massive public, scandalous sin that all can see and gossip about. It’s the spiritual struggle so imposing that you can’t even see how high it is or know how hard it will be. Consider a time in life when a mountain stood before you, and then Jesus says these words: “Just this much faith is all you need.”
The Mulberry Tree from Luke 17, on the other hand, is the hidden spiritual challenge: the covered, complex difficulties. Or the secret sin that, though not publicly scandalous, is ever elusive and just when you think you’ve got a hold of it, it arises someplace else. The mulberry roots are the parts of us that no one may ever see, but the more we examine ourselves the more difficult they are to uproot and unwind. Sometimes we don’t even know where to start or where it will all end. Consider a time in life when you were so overwhelmed by the dozens of details to sort out; or a conflict so complex you didn’t even know where to begin, and then Jesus says “one little seed of faith” is enough.
Mountain or Mulberry tree? Which would you rather have to move ½ mile east into Lake Michigan this morning? You could make a case for either: at least the mountain is one big mass. I know what it is and where it is… but it just so overwhelming. The mulberry tree’s roots are smaller, less intimidating, I can even get my hands on them… but on the other hand there’s so many, and they slip out of my fingers, and just when I think I’m done there’s a dozen more to be uprooted.
In both examples, the mountain in Matthew 17 and the mulberry tree in Luke 17, Jesus both rebukes and redirects his disciples — and he does the same for us. He rebukes us because we think that when it comes to faith, size matters. Amount matters. Quantity counts. As if you can just throw yourself with eternal optimism at the big ol’ mountain and run into it with reckless abandon and you’ll push ½ mile east. You can’t. As if just believing in something hard enough or long enough or with continued fervor will pull up all the roots and solve the problem. It won’t.
The disciples’ misunderstanding of faith was that they thought faith was about spiritual energy they would exert (Lord, increase our faith). But Jesus wants them to think instead about where it would be directed. They, like us, liked to trust in themselves and their own abilities or powers; or they would trust in the rules and laws and rituals of their religion; or they would trust in princes, politics, or policies; or in each other, or in their own piety, or in their own strength.
But Jesus redirects them and their faith solely into himself. If faith is planted in the right place, its size or strength matters not at all. If faith is sunk solely into Jesus, his work, his person, his power, then no mountain is too massive and no root system to complex. Jesus in these spiritual gut punches from Luke confronts us with seemingly impossible spiritual activities and attitudes, in order to teach us that faith, no matter its size, is only effective when it’s directed towards him. With man it is impossible, but not with God. With God all things are possible. So it’s not the size or strength of your faith that matters; it’s where you place it that counts.
Jesus redirects the disciples’ faith towards himself and him alone because the Lord knows where it all will lead: to the cross, where every sin is forgiven and every suffering is given meaning; to the resurrection, where not even death itself can outweigh his love; to his righteous life lived for us, on our behalf, given in exchange for us; to his eternal rule in glory, where we know he is at work in all things for our good. No tragedy is too large for his strength; no sin too intractable for his grace; no situation above or beyond his rule. Faith in Jesus, no matter how large or small, or powerful or weak, moves both mountains and mulberries because it’s Jesus who’s doing the moving.
Friends: if there hasn’t yet been, there will be a mountain that stands before you. Say not, “How can I use my faith to move this mountain?” Rather say, “Lord, what little, wavering, flickering faith I place in you, and you alone.” And you’ll discover a mulberry tree in your life or heart one day too. Say not, “How can my faith remove each root?” Rather say, “Lord Jesus, your cross, your forgiveness, your grace, your faithfulness are enough. In you alone I trust, though undeserving I am and though I cannot see how this will all work out.”
All faith, no matter how strong or weak, no matter how consistent or faltering, place it in him.
Come soon Lord Jesus. Amen.
[1] I’m grateful to Dr. Scott Bruzek for this turn of phrase.