Matthew 16:6. “Then Jesus said unto them, Take heed and beware of the leaven of the Pharisees and of the Sadducees.”
I’ve been baking most of the bread for my household for 45 years now. I’ve learned quite a bit about the process. I know, for instance, that it takes only a tablespoon of dry yeast to give me two big, beautiful loaves of bread. There can be anywhere from six to eight cups of flour in those loaves, plus milk, maybe 2 cups, and a tablespoon of sugar to “feed” the yeast. Add a little salt and oil, and you have some really good bread. Smells like heaven when it’s baking 🙂
So what does that have to do with this verse?
Well, think about the small amount of leaven (yeast) that is required to affect 6-8 cups of flour. Not very much, and yet when the yeast is introduced into the flour mixture, and gets a little bit of sugar to activate and feed it, the yeast totally changes the character of the bread. Without the yeast, the bread would be flat. It would not rise. It would be very heavy, and not particularly appetizing.
In Bible symbolism, leaven is not usually a good thing. When God demanded purity in sacrifices and/or feasting, He always specified unleavened bread. A little leaven affects the whole lump of dough, just as a little sin affects the truth of God’s Word as well as the purity of our lives.
The false teachings of the Pharisees and Sadducees had created great confusion. Strict adherence to traditional law, not necessarily God’s law, had made the Pharisees seif-righteous and legalistic. Incorrect interpretations of the Sadducees had created false doctrine including a rejection of the resurrection of Messiah. My dad used to say that the Sadducees didn’t believe in the atoning death and resurrection of Jesus, and that is why they were sad, you see? Kind of corny, but it helped me remember.
So. Jesus took the irresponsibility of the disciples, who had forgotten to purchase bread, and turned it into a teachable moment. A little bit of false teaching can completely change the character of the gospel as well as the character of those who accept the lie along with the truth.
The song in Mary Poppins says that a spoonful of sugar helps the medicine go down. So that spoonful of sugar in the bread mixture feeds the yeast, causes it to bubble and grow, and sweetens the final product. In bread, that’s a wonderful result.
In changing the truth of God’s Word, the sugar and the yeast are poison.