The Yeast – Sermon – Pastor Dave Page

It sounds like a fairly ordinary kitchen scene doesn’t it? And yet Jesus gives us one of the clearest pictures in all of Scripture of how God changes people. Not from the outside in but from the inside out.

The Incredible Power of Something Almost Invisible

“The Kingdom of heaven is like yeast ” Over the past year I’ve discovered that making sourdough bread is really less about baking and more about biology.

When I first started, I thought I was learning recipes. Instead, I found myself reading about microbiology. Temperatures, hydration percentages, fermentation times, wild yeast, lactic acid bacteria. Things I never imagined I’d care about. And one of the biggest surprises was learning just how incredibly powerful yeast really is. To the naked eye, it seems insignificant. You can’t see an individual yeast cell. In fact, a single yeast cell is only about five to ten microns across. To put that into perspective, you could line up nearly twenty yeast cells across the width of a single human hair. They’re microscopic, pretty much invisible to the naked eye. And yet, inside a single packet of baker’s yeast are billions of living organisms. Even a sourdough starter contains an astonishing community of wild yeast living alongside beneficial bacteria, all working together.

What amazed me even more was discovering what those tiny organisms actually do. They don’t simply “make bread rise.” Each microscopic yeast cell feeds on the natural sugars released from the flour. As it feeds, it releases carbon dioxide. Millions, then billions of tiny bubbles begin forming throughout the dough. Those bubbles become trapped in the gluten network, stretching it little by little until an ordinary lump of flour and water is transformed into a light, beautiful loaf of bread. Here’s the remarkable thing about that process, none of that happens where you can see it. You don’t really watch the yeast at work. You don’t hear it. You can’t force it. You simply trust the process.

When I mix my dough together, there are times I’ll come back after thirty minutes and think, “Nothing’s happening.” Then another hour later, “Still doesn’t look much different.” But all the while, billions of tiny living organisms are quietly changing everything from the inside.

The transformation was never absent, I just couldn’t see it. So many of us assume that if we can’t see God working He must not be working at all. We pray for healing. We seek freedom from an old habit. We ask God to restore a relationship. We serve, We forgive, We obey. And because we don’t immediately see dramatic results, we start asking questions. “Is anything actually changing?” I think Jesus would gently smile and point to the dough sitting on the counter. Nothing spectacular appears to be happening. But beneath the surface life is multiplying. Transformation is underway. And given enough time what was once dense and lifeless becomes something entirely new. That is how the Kingdom works. Most of the time. Not with noise or grand spectacle, But with quiet, persistent, life-giving power that works from the inside out.

And that leads us to one of the most important truths in this little parable. The Kingdom isn’t just like yeast because it’s small, that’s where this parable is different than that of the mustard seed. I think Jesus uses yeast because God is far more interested in changing what is happening inside us than merely improving what people see on the outside.

God Works From the Inside Out

Matthew says, “A woman took and mixed into about sixty pounds of flour…” The word translated “mixed” is remarkably strong. The Greek word ἐγκρύπτω (enkryptō) literally means: “to hide inside.” The yeast disappears. It becomes invisible. Yet from that hidden place it changes everything. That is exactly how God’s Spirit works.

Religion often focuses on behaviour. Jesus focuses on the heart. Religion says: “Look different.” Jesus says: “Become different.” Because whatever fills the heart eventually shapes the life. Jesus repeatedly taught this. “A good tree bears good fruit.” Not because someone tied fruit onto the branches but because life flowed from the inside.

The Promise Was Never Better Behaviour

This is exactly what God had been promising His people for hundreds of years. Listen to what He says through the prophet Ezekiel. “I will give you a new heart and put a new spirit in you; I will remove from you your heart of stone and give you a heart of flesh.” (Ezekiel 36:26)

To appreciate the beauty of this promise, we need to remember when God spoke these words. Ezekiel was writing to the people of Israel while they were living in exile in Babylon. Jerusalem had fallen. The Temple had been destroyed. The people had lost their land, their identity, and, in many ways, their hope. But their greatest problem wasn’t Babylon—it was their own hearts. For generations they had drifted from God, chasing idols and relying on outward religion while their hearts had grown cold toward Him. So God didn’t simply promise to bring them back home. He promised something even greater. He said, “I will give you a new heart and put a new spirit within you.” In other words, “The future I’m preparing for you isn’t just about a new location. It’s about a new transformation. I’m going to change you from the inside out.”

Notice what God doesn’t say. He doesn’t say, “I’ll help you try a little harder.” He doesn’t say, “I’ll give you a better list of rules.” He doesn’t say, “I’ll improve your behaviour.” No, He says, “I’m going to change your heart.” Because God has always understood something we often forget. Our greatest problem isn’t simply what we do. It’s who we are. Think about that for a moment.

If you’ve ever pulled weeds in your garden, you know you can cut the tops off, and for a few days everything looks clean. But if the root remains the weeds simply come back. Behaviour is often the visible part, but the heart, for a human, is always the root. Jesus taught exactly the same thing. He said that evil thoughts, anger, lust, greed, pride, and selfishness don’t come from somewhere outside of us. They come from within. Which is why the Kingdom doesn’t begin by trimming branches. It begins by changing roots.

From Stone to Flesh

I love the picture Ezekiel uses. A heart of stone. Think about what stone is like. Cold, Hard, Unresponsive. It doesn’t feel. It doesn’t bend. It doesn’t grow. Then God says, “I’m going to replace that with a heart of flesh.” Something living. Something that can respond to Me. Something that can be shaped by My Spirit. Notice the language. God doesn’t renovate the old heart, He replaces it. That’s the language of new creation. Hundreds of years later Paul writes these remarkable words: “Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come.”(2 Corinthians 5:17) He doesn’t say, “God has given you a spiritual tune-up.” He says, “You are a new creation.”

The Greek word Paul uses here, kainos, means new in kind. Something qualitatively different, something transformed. This isn’t God repairing broken machinery. It’s the Creator doing what only the Creator can do. Creating life where there wasn’t life before. That’s why becoming a Christian isn’t simply adopting Christian morals. It isn’t becoming more religious or learning Christian vocabulary. It is receiving an entirely new source of life.

That’s How Yeast Works

Now, if you’re tracking along with me then suddenly, Jesus’ illustration makes perfect sense! The yeast doesn’t improve the dough from the outside. It enters it, Lives within it, Transforms it. Everything that happens on the outside is the result of what first happened on the inside. That’s exactly how the Holy Spirit works too.

The Spirit doesn’t simply teach us to act differently. He begins reshaping our desires. He changes what we love and value. The longer we walk with Christ, the ore we discover that the greatest miracle isn’t simply that we behave differently. It’s that we begin wanting different things. We start loving what Jesus loves. We begin forgiving more quickly and serving more freely. Trusting more deeply. Not because someone is forcing us from the outside but because God is quietly transforming us from the inside.

This past week while we were away on vacation, we stayed in a lovely Airbnb. When you first walk into a place like that, you notice all the obvious things. The décor. The furniture. The comfortable beds. Everything is arranged to make a great first impression. But after you’ve lived there for a few days, you begin to appreciate something else. What really makes the place enjoyable isn’t the things you immediately see. It’s what you don’t notice. The plumbing works, The electrical system is reliable, The air conditioning keeps running, The hot water is there every morning. You don’t spend your vacation thinking about those things because they’re quietly doing exactly what they were designed to do. In fact, if you do start noticing them it’s usually because something has gone wrong!

The beauty on the surface is only possible because something deeper is working underneath. And I think that’s exactly what Jesus is teaching us. So often we ask God to make our lives look better on the outside. “Lord, fix my circumstances.” “Fix my relationships.” “Fix my stress.” But God often begins somewhere much deeper. He starts with the foundation, He works on the heart. Because He knows that if the heart is transformed, eventually everything built on that foundation begins to change as well.

Let me show you one last thing here, Because Jesus isn’t finished. The yeast doesn’t simply change one part of the dough. It changes everything.

Transformation Always Spreads

Jesus says the yeast worked “until it was all leavened.” Not part. All.

That phrase matters to us in this discussion, because God’s intention has never been partial transformation. He is after the whole person. Here’s something fascinating. The woman mixes the yeast into three measures of flour. That’s roughly forty litres enough bread to feed over one hundred people. Jesus intentionally exaggerates for this reason. A tiny amount of yeast affects an enormous amount of dough.

One hidden influence, Massive impact. The Kingdom works exactly like that.

• One faithful parent.
• One teacher.
• One act of forgiveness.
• One prayer.
• One church
• One conversation.

Tiny beginnings, Kingdom-sized outcomes.

Many of history’s greatest movements began quietly. The abolition of slavery. Hospitals, schools, Bible translation, Mission movements. Most began with ordinary believers doing small things faithfully. No headlines. Just yeast. That leads us to perhaps the most personal question this morning. Where is God trying to do hidden work inside us?

Invite God Into Hidden Places

Throughout this series we’ve discovered something remarkable. The Kingdom is often hidden in plain sight. Today, Jesus reminds us the deepest work is hidden inside us. There are places no one else sees, you know these places well, we all do. Our private fears and hidden resentments. Secret pride, Quiet disappointments, Unspoken grief, Lingering shame. Jesus doesn’t expose those places to embarrass us. He enters them to transform us.

Psalm 139

“Search me, O God and know my heart.”

David understood something. Transformation begins with surrender. Not performance. Here’s our encouragement for you this week: Think about bread again. The dough cannot make itself rise. It simply yields to the work of the yeast already inside it. Likewise our spiritual growth is not manufactured by striving. It comes by yielding ourselves to the Spirit of God. Paul describes it this way in Philippians 2: “It is God who works in you…” Look closely at Paul’s words. Not merely for you. Not merely through you. In you.

This week, simply notice and take inventory of where God has been quietly reshaping your character.

• Is it your compassion?
• Is it your patience.
• Is it your humility or self-reliance.

Those are Kingdom miracles too.

Sometimes the greatest evidence that Jesus is changing us isn’t that life becomes easier. It’s that we become different. I encourage you to spend time with that this week. This week, instead of asking, “God, change my circumstances,” perhaps begin with, “God, change me.” Invite Him into the hidden places. Because the Kingdom has always worked from the inside out.