Title: “Watch Out for the Yeast!”

Scripture text: Mark 8:14-21

Main point: Sin, left in the heart without repentance, grows bigger and hurts more people.

Preparation: In your “Bag of Wonders” hide a dinner yeast roll, some unleavened bread, and a package of baker’s yeast.

Opening question: Have you ever heard of yeast? (interact with the children’s answers)

Message: Yeast is something your mom or dad or grandmother or the baker in the grocery store uses to bake bread. And the Bible talks about yeast a good bit too. Let me show you what yeast does. (Pull the yeast roll and unleavened bread out of your Bag of Wonders.) Both of these are types of bread. But they are different, aren’t they? What’s the difference between them? (Children will say one is flat and one is big and puffy.) Do you know why this roll is big and puffy? It’s because of this. This is yeast. (Show the package of yeast.) Yeast is actually a fungus. It’s little microorganisms that cause bread dough to rise. When someone wants to bake bread, she mixes a little bit of yeast in with the flour, water, sugar, and salt. Then she takes the dough and puts it in a warm oven for a while. Slowly but surely, the yeast causes air bubbles to form inside the dough. The dough gets bigger and bigger and bigger. That’s what made this dinner roll so big and light and yummy. But this flat piece of bread did not have any yeast in it. So it stayed real flat.

The Bible talks about yeast. Usually when God talks about yeast in the Bible, it’s because he wants us to think about sin. Now just so you know, yeast is not bad. Yeast makes bread taste good. But in the Bible, yeast is often a symbol for sin. That’s because when you let sin stay in the heart, without confessing it to God or other people, it gets bigger and causes greater and greater damage. In Mark 8:14-21, Jesus told his disciples, “Watch out for the yeast of the Pharisees!” He didn’t mean to watch out for the kind of yeast your mom uses to bake bread! He was talking about sins like hypocrisy and false teaching and lying and things like that. When you tell a lie, for example, it often leads to other lies. The more lies you tell, the more likely it is that you or someone else is going to get hurt.

Let me tell you a story about a little boy I’ll call Timothy. His dad took him fishing one Saturday, and Timothy caught a fish. It was a little fish about 6 inches long, but Timothy was proud of himself. On Monday when he wen
t to school, he told one of his friends he caught a fish that was a foot long. Later, he told another friend he caught a barracuda three feet long. Later that week, he told another friend he caught a shark! Still later he told someone he caught a whale! When his father found out what Timothy was telling people, he said, “Timothy, have you been lying? What’s this I hear about you catching a whale?!” Timothy was very sad. He realized he should have confessed his first lie, because his fish story got bigger and bigger as time went on.

Sin is like yeast. It makes problems grow and grow. Watch out for the yeast! Confess your sin as soon as you’re aware of it. Turn away from sin and repent. You know why it’s OK to tell God and other people about your sin? Because Jesus’ love is a lot bigger than your sin! Jesus died on the cross not only for the sins you’ve committed in the past, but the sins you’ll commit today, tomorrow, and in the future. Proverbs 28:13 says, “Whoever conceals his transgressions will not prosper, but he who confesses and forsakes them will obtain mercy.”