Then Jesus said to them, “Take heed and beware of the leaven of the Pharisees and the Sadducees.” (Matthew 16:6)

A few years ago, a twelve year-old boy in Fountain Valley swapped food with a schoolmate during lunch. He nibbled on a protein bar, and almost immediately complained of itchy hands and pain in his ears. Seven minutes after biting into the bar, the boy was dead. He was allergic to peanuts, and thought the bar was peanut-free but it wasn’t, and it killed him.

It is amazing how such a little thing can have such huge results. People are becoming more aware of peanut allergies, and some schools have even banned peanut butter sandwiches at school lunches, so no kid will swap with another child who may have a peanut allergy.

Jesus knew all about the principle of a little mistake meaning a lot, and He spoke to His disciples about it in Matthew 16:5-11. Jesus and the disciples were traveling, and since this was a few thousand years before the invention of the drive-through or the convenience store, it wasn’t always easy for travelers to find food. So when Jesus warned His disciples about the “leaven of the Pharisees and the Sadducees,” the disciples thought it was all about an ill-planned menu. Jesus knew there was something more important than food, so He warned against the leaven of the Pharisees and the Sadducees.

Leaven is what we would call “yeast” – it makes dough rise. Many years ago I decided to bake some oatmeal cookies, and the recipe called for a teaspoon of baking powder. I supposed I didn’t read the recipe too well, because I put in a tablespoon. There isn’t a whole lot of difference between a tablespoon and a teaspoon – unless you are using leaven. They came out terrible, because a little mistake can mean a lot.

At first glance, it’s hard to see that the Pharisees and the Sadducees had anything in common. They certainly didn’t like each other. The Pharisees were the “back to the Bible” movement of their day, and most people thought they were super spiritual. The Sadducees were the establishment “fat cats” who pulled the strings of political and economic power. The disciples couldn’t figure out why Jesus told them to beware of their “leaven,” but the answer is in Matthew 16:12: “Then they understood that He did not tell them to beware of the leaven of bread, but of the doctrine of the Pharisees and Sadducees.”

What was so wrong with the doctrine of the Pharisees and Sadducees? At first light they had nothing in common; they disagreed on so much. At a closer look they had several things in common.

· They both rejected Jesus

· They both thought they could save themselves apart from Jesus

· They both thought they were good enough without Jesus

If you quizzed the Pharisees and Sadducees about theological facts, you would find that they both had a lot of good beliefs – but you can believe a thousand true things, yet one crucial mistake can mean the ruin of everything. If you travel in one degree off from your destination you may never reach it. Are you infected with the leaven of the Pharisees and Sadducees?

The doctrine of the Pharisees and Sadducees – the idea that we don’t really need Jesus – is enough to ruin anyone. We may believe a hundred right things, but if we miss this we miss everything.