A Little Leaven

“A little leaven leavens the whole lump.” (Galatians 5:9, ESV)

In high school biology, one of the projects we had was to grow a yeast culture. It was an interesting project. Frankly I do not remember all the details of how we did this today, but I do remember sampling the culture every day and counting the yeast cells.

To measure the cells, we would take a sample and smear it on a microscope slide, apply some methylene blue dye, and count the cells using the microscope. It was amazing to see how the yeast cells multiplied over time. What began as just a few multiplied rapidly to a large number.

Yeast is a leavening agent often used in baking. It causes the fermentation that puts the air holes in baked bread. In this sense it is good. Metaphorically, the yeast or leaven can be used to describe anything that begins in a small amount that rapidly grows and spreads.

In ancient times bakers would maintain a starter. It was basically a yeast culture in some dough. When they were to bake a loaf, they would take the starter, the leavened dough, and put it in the new unleavened dough. After kneading the starter into the new dough, the yeast would rapidly multiply and spread through the entire batch of dough causing it to rise for baking.

Paul used this familiar metaphor to deal with a serious issue facing the Galatians. He referred to the false doctrines of the legalists as “leaven.” The congregation need to clearly understand the danger of letting the doctrine continue unabated in the church. With this metaphor that this false doctrine would naturally grow and affect the whole assembly to their detriment. They needed to take aggressive measures to eliminate the leaven of the legalists before it influenced the whole group.

Here is the issue. Sometimes, when false teaching comes into a church, it may seem like a small thing. Someone will come in who has a dynamic character and to whom people will listen. This person will espouse a teaching that is counter to the truth. Sometimes the church leaders do not even know it is happening. So, people listen and begin being persuaded to this new teaching. Eventually, this seemingly small issue with one person has influenced the entire church. Often this is seen in factions that rise up in the church, causing dissension and other ills, which undermine the true teaching of the Scripture.

When I pastored, I ran into this same problem on several occasions. Two things I learned about this. First, by the time the pastor hears of it some of the damage is already done. Generally, the false teachers pick off those younger in the faith who are not fully grounded in the Word.

Second, you cannot allow false teaching to go unchecked, no matter how insignificant it may seem. When left unchecked it will spread adversely affecting the health of the church. It will be like a contagion that will spread unless contained.

What are church leaders to do? First, disciple all believers so that they can discern biblical doctrine and exercise discernment in what they hear. Second, when false teaching is identified, leaders must respond rapidly to deal with and eliminate it.