Jesus once said, “The kingdom of heaven is like leaven that a woman took and mixed in with three measures of flour until all of it was leavened” (Matt. 13:33). My youth group contemplated this while we mixed together some warm water, sugar, and yeast. It didn’t take long for the yeast to form a large mound of bubbles and let off the smell of fermenting sugar.

Bread-making is a familiar process for our young people. I’m a pastor and youth leader in a small rural church in Upstate New York, where most of our young people’s families raise poultry, cultivate vegetables, and often make their own bread. They knew what Jesus was trying to say here. All you need is a little bit of yeast - just 1 to 2 teaspoons - and you can get multiple loaves of bread to rise. Likewise, the natural process of the kingdom of heaven is growth. As we looked at this passage, we talked about how God wants growth for our lives, both in the size of our group (evangelism) and in the quality and depth of our faith (discipleship). This was an easy parable for our youth group to understand. It’s no wonder that just a few verses later in Matthew 13, we read that Jesus taught in parables to reveal life’s hidden mysteries. Jesus was creative in his teaching to make the Gospel clear and relevant.

But that wasn’t the only time Jesus used yeast figuratively. He also said, “Watch out, and beware of the yeast of the Pharisees and Sadducees” (Matt. 16:6). This saying is not quite as easy to understand. What makes some yeast good and some yeast bad? Understanding this saying is actually quite important for understanding why Jesus spoke in parables and why our own language about God should evolve and remain creative.

Jesus and his Jewish audience understood something that eludes many modern Christians: the Passover prescriptions of Exodus 12. Every year, Jews would throw out their old yeast and start with fresh yeast. Additionally, the barley harvest occurred shortly after Passover, which provided an opportunity to start a new leavened lump of dough made from flour from the new harvest God had provided. This did two things. First, it removed unsanitary dough that could cause harm. In addition to collecting yeast fungus, a leavened dough lump could also collect other bacteria that wasn’t safe to eat. Second, it acknowledged that God was presently doing something among the people by providing a new harvest. The “yeast” of the Pharisees that Jesus warned his disciples about was traditionalism: holding on to the old ways for the sake of the old ways.

In other words, the Pharisees hadn’t updated the conversation about God, and it was having detrimental effects.

Here’s what it means when we tie these two passages together: Our ministry with young people should introduce them to a living and dynamic faith that flows out of our own relationships with Christ and seeks to grow in them. The faith that we model and that we nurture in our young people should also incorporate regular self-evaluation. Without refreshing our faith and staying aware of what God is doing in the present moment, the very same faith that was once dynamic and growing can become dangerously harmful to us and the people we share it with, just like old leaven that hasn’t been replaced.

For my young people, this might mean not just understanding their faith in terms of the parables that make sense in their rural context, but also refreshing their conversation by learning what faith can look like in an urban context, or in a more multicultural context, or in a foreign context. Faith can be enlightened through many different and creative ways of thinking. Faith can make sense anywhere.

Listen to the Open Me Disruption podcast with Youth Worker Pete Croall exploring the reflection from this week.