Parable of the leavened dough illustrates the secret to lasting change using yeast
e told them still another parable: "The kingdom of heaven is like yeast that a woman took and mixed into a large amount of flour until it worked all through the dough." (Matthew 13:33 (NIV)
Many people, not just Christians, but other good people as well, look at the problems in our world, and are almost immediately overwhelmed by the magnitude of brokenness. They see wars, poverty, disease and even man's inhumanity to man, and can be driven almost to despair. "How can I possibly do anything to change things? I'm only one person!"
In this parable about small beginnings, Jesus moves his focus off of potential, and deals instead with a methodology that holds within it the secret to lasting change.
The people of Jesus' day had no idea how yeast worked. They only knew that if a small piece of leavened dough, held aside from the previous batch, was added to a new batch of dough, the leaven would spread through the new batch, and soon the whole thing would be leavened.
Today we know that yeast is a variety of fungus that feeds on starches, like sugar, and produces gas bubbles that raise the dough as a byproduct. However, the focus of the yeast cells is not on producing the gas bubbles that we value so much, but on simply reproducing themselves. The individual cell consumes the starch, metabolizes the nutrients, produces a small bubble of gas and divides in two. The process is then repeated by both the old cell and the new, resulting in four cells. And so the process continues, and the multiplication of the cells continues exponentially until they run out of food, or are killed by the heat of the oven when the loaf is baked.
The yeast, in the process of doing what it does — reproducing itself — changes the whole character of the loaf. The yeast cells aren't trying to change the character of the loaf; the change occurs as a simple byproduct of their focus on multiplication.
In the same way, the people of the kingdom of God have one purpose given to them by Jesus: to multiply themselves. "Go and make disciples of all nations." (Matthew 28:19) They are to feed on their relationship with God through Jesus, and on God's word to them. Then they are to take all of that energy and use it to reproduce themselves in the people all around them. Like the yeast, they don't have to reproduce themselves hundreds at a time (although that can happen from time to time). All it really takes is for each disciple to reproduce themselves by making one new disciple who can reproduce themselves, and then start the process all over again, and, over a surprisingly small interval of time, the growth will be exponential.
Like the yeast, the focus of disciples should never be on changing the society in which they live. That focus could easily overwhelm even the staunchest disciple. Instead, the changes will take place in a society as a natural result, a byproduct, of the multiplication of disciples, until the entire society is transformed. That's why Jesus didn't say, "Go and change the world," but "Go and make disciples of all nations."