As I read through the Bible, I often see comparisons that I had not previously considered. Recently, I noted a couple of different times and different ways that Jesus used the analogy of leaven. The two uses of the term, leaven, contrast with each other in interesting ways.
In Matthew 13, Jesus used the term in telling a short parable about the kingdom of God. Later, in Matthew 16, Jesus used the term in speaking about the influence of the Pharisees. They appear in the ESV as follows:
“He told them another parable, ‘The kingdom of heaven is like leaven that a woman took and hid in three measures of flour, till it was all leavened.’” (Matthew 13:33)
“When the disciples reached the other side, they had forgotten to bring any bread. Jesus said to them, ‘Watch and beware of the leaven of the Pharisees and Sadducees.’ And they began discussing it among themselves, saying, ‘We brought no bread.’ But Jesus, aware of this, said, ‘O you of little faith, why are you discussing among yourselves the fact that you have no bread? Do you not yet perceive? Do you not remember the five loaves for the five thousand, and how many baskets you gathered? Or the seven loaves for the four thousand, and how many baskets you gathered? How is it that you fail to understand that I did not speak about bread? Beware of the leaven of the Pharisees and Sadducees.’ Then they understood that he did not tell them to beware of the leaven of bread, but of the teaching of the Pharisees and Sadducees.” (Matthew 16:5-12)
So, the kingdom of God is like leaven, but there is a “leaven of the Pharisees and Sadducees” of which we should beware. The leaven that is the kingdom of God is good, but the leaven of the Pharisees and Sadducees is bad. What is Jesus talking about?
I find it interesting that the disciples took Jesus literally when he said, “beware of the leaven of the Pharisees and Sadducees.” We read what Jesus said and intuitively know that he isn’t talking about literal leaven. It’s a metaphor.
I suppose it’s understandable, though. They had just crossed the lake, and they suddenly realized they forgot to make any provision for food. Their stomachs were probably starting to growl. What else would you be thinking about in that moment?
That’s where our mind naturally goes, doesn’t it? If you are like me, you are often thinking about the next meal. Jesus had just gotten done with the instruction on the other side of the lake. Now it was time to relax (at least for a while), but they had no food.
Do you get the impression that Jesus never stopped thinking about the kingdom of God? I certainly do. Food or no food, hungry or not, Jesus seems to have always been focused on the Father and His kingdom. We are very easily distracted, on the other hand.
Perhaps, the most extreme example of the human tendency to distraction was in the garden of Gethsemane. Jesus had repeatedly warned the disciples that he would be giving his life up soon. They just had eaten the “last supper” where Jesus had said some extremely odd things about his body and blood: Judas was called on the carpet and left in hurry; something was clearly up, as Jesus urged them to pray while he went off on his own. Yet, they couldn’t stay awake.
When we read this passage, we should try to put ourselves in the disciples’ shoes and imagine what they were thinking and feeling. What seems obvious to us, reading this passage short like ancient history, was obviously not so obvious to the disciples at the time.
What things are not so obvious to us today that might be obvious to someone else in retrospect?
While this gets a bit off topic, I would suggest we may have a blind spot regarding how we read Scripture. A significant segment of Bible believers cling to reading Scripture literally, especially when it comes to certain passages, like Genesis 1. They would say that we must interpret “day” “literally”, as a 24-hour period of time, rather than more figuratively, as an undefined period of time (like “back in my day” or “in the day of the dinosaurs” or “in Jesus’s day”).
But, I digress (only slightly). Just as Jesus was always focused on the Father and the kingdom of God everywhere he went and in everything he did, God is always “talking” to us. God isn’t distracted by hunger or other things. He is always engaging (and ready to engage) us, but we aren’t always “tuned in” to hear Him.
When Paul tells us to “pray without ceasing”, maybe this is partly what he is talking about: being mindful always to turn towards God and tune in to what He is saying. We are easily distracted in our circumstances, so we need the reminder to pray without ceasing.
From the order in which the two uses of the word, leaven, were used in Matthew, we might assume that Jesus first spoke about leaven in relation to the kingdom of God: “The kingdom of heaven is like leaven….”
This makes sense, as Jesus spent the early part of his public ministry in remote places speaking to crowds of common people. The religious leaders heard about what Jesus was preaching, and they eventually began to confront him, but Jesus spoke in remote places before he ended up in Jerusalem.
The word translated “leaven” in Greek is ύμη, ης, ἡ (zýmē). It literally means leaven, ferment (or yeast). Figuratively, it means “the spreading influence of what is typically concealed”.
As a general proposition, the idea of leaven is something that is small in quantity, but its influence thoroughly influences or pervades something that is much larger. It is a catalyst that, while very small, changes the character of the primary thing it affects.
Yeast leavens bread and ferments alcohol by acting on the sugars in each mixture, producing different results by similar biological processes. Yeast metabolizes and breaks down sugars, releasing carbon dioxide in the process. The carbon dioxide is a waste product that produces the effect of dough rising and drink fermenting.
The leavening of bread and fermenting of drinks are obviously beneficial processes. Leavened bread is much more palatable, enjoyable and useful than unleavened bread. Fermented drinks are used in weddings and other joyous occasions, with meals when people break bread, and were often used in the past as alternatives to water from contaminated sources.
Thus, leaven can produce good and beneficial results in the right contexts, but “leaven” can be also a corrupting agent that produces a negative influence. The principles act the same way. Corrupting agents may be relatively small but have a dramatic, negative influence on the whole. (We might use a more modern term, like an infection, to convey the same idea.)
Interestingly, the figurative meaning seems to have been more often used in the negative. For instance, when Paul said, “A little leaven leavens the whole lump”, he was talking about a little sin in a church can corrupt the whole church. (1 Cor. 5:6) He also talks of the leaven of sin in Galatians 5 about corrupting ideas.
In Galatians, the leaven Paul identifies is a false gospel:
“You were running a good race. Who cut in on you to keep you from obeying the truth? That kind of persuasion does not come from the one who calls you. ‘A little yeast works through the whole batch of dough.” (Gal. 5:7-9)
The Galatians were being swayed by fellow Jews to submit to the requirement of circumcision. They were ultimately seeking to be justified by the law, which was alienating them from Christ (Gal. 5:4) who fulfilled the law and offers justification by grace that can be accepted through faith. The leaven of this false gospel was causing confusion and corrupting the church in Galatia.
The leaven Paul identifies to the church in Corinth is sinful attitudes and behavior:
“Your boasting is not good. Don’t you know that a little yeast leavens the whole batch of dough? Get rid of the old yeast, so that you may be a new unleavened batch—as you really are. For Christ, our Passover lamb, has been sacrificed. Therefore let us keep the Festival, not with the old bread leavened with malice and wickedness, but with the unleavened bread of sincerity and truth.” (1 Cor. 5:6-8)
I little boasting, a little malice and wickedness, has a negative, corrupting effect on everyone involved in the church. How we act (allowing sinful attitudes and behaviors to exist) can have a leavening effect on a church. Thus, the leaven of sin can corrupt a congregation just as much as the leaven of a false gospel.
I note here, that Paul urges remaining unleavened in this context. It is better to remain pure and unleavened than to be puffed up with the leaven of sin!
Going back to the contrast, Jesus used leaven first in a positive sense. The kingdom of God has a leavening effect in us and in the world. It is similar to the idea that followers of Jesus are salt and light in the world.
This metaphor suggests that the kingdom of God is not necessarily noticeable. Like yeast, you don’t know that it is in the bread or in the beer, except for the results you can see.
The leaven gets incorporated into the brad or drink, and it goes to work our of sight. It doesn’t even bring attention to itself, except for the beneficial result it produces. A person who doesn’t know about yeast and how it works would not even make the connection.
Followers of Jesus are in the world, but not of the world. We can only affect the world in the positive way God intended if we are different from the world.
Neither yeast nor salt calls attention to itself. Yeast works by consuming sugars and eliminated carbon dioxide as a waste product. If the analogy fits, the sugar would be sin. The waste product is the self that is being crucified with Christ. When we take up our crosses to follow Jesus, we are submitting to this process of dying to self to allow Christ to live in us and for God’s kingdom (the yeast) to have its way in us.
This happens on an intimate, personal basis in the hearts of believers and in the body of Christ as we live out a life submitted to Christ who died for us. The effect it has on the world is similar to the rising of bread and fermenting of wine.
We live in a fallen, corrupted world. Jesus came bearing witness to the good news of the kingdom of God. He came to die and to invite others to follow him. This is the leaven that is the kingdom of God in the world.
We must be ever vigilant to keep the leaven of the Pharisees, sin and false gospels out of the body of Christ. If we allow these things to creep in, the church becomes just like the world, and it no longer has its intended effect on the world.
We need to remain salty; salt that has lost its flavor is good for nothing.