Sayings Of Jesus: Leaven
Here’s a question. When the New Testament speaks of “leaven,” is that a positive thing, or a negative thing? The short answer is that it’s both! Or rather, it can be either. Intrigued? Read on.
Let’s start by defining our terms. According to a typical dictionary definition (Merriam-Webster.com), “leaven” is a substance used to produce fermentation in bread making (causing the dough to rise). Baking powder and yeast are familiar examples of leavening agents. Our word derives from the Latin word levare, meaning “to raise” (from which we also get “lever”) or “to lighten.” In that second sense, the word is used metaphorically, as in “The sermon was leavened with humor.” Usually unsuccessfully, in my case, but you get the idea.
How, then, does leaven “work”? The ancients would have understood the effect but not the science, which is down to enzymes.
Many of us will have come across leaven in the context of its opposite—“unleavened” bread. The typical bread we buy at a baker’s or supermarket is leavened; examples of unleavened bread would be rotis and tortillas.
The Feast of Unleavened Bread is adjacent to Passover in the Jewish calendar. Since unleavened bread features in both festivals, the two were combined shortly before the Exile (with the terms often being used interchangeably).
The Feast of Unleavened Bread is mentioned several times in the New Testament (Matthew 26.17; Mark 14.1, 12; Luke 22.1, 7; Acts 12.3, 20.6). For seven days, the Israelites were to eat only unleavened bread (Exodus 12:15-20; 13:3-7). Why might that be? Exodus 13:3-7 seems to offer the clearest starting point for the rationale:
Moses said to the people, “Remember this day in which you went out from Egypt, from the house of slavery; for by a powerful hand the Lord brought you out from this place. And nothing leavened shall be eaten. On this day in the month of Abib, you are about to go forth. It shall be when the Lord brings you to the land of the Canaanite, the Hittite, the Amorite, the Hivite and the Jebusite, which He swore to your fathers to give you, a land flowing with milk and honey, that you shall observe this rite in this month. For seven days you shall eat unleavened bread, and on the seventh day there shall be a feast to the Lord. Unleavened bread shall be eaten throughout the seven days; and nothing leavened shall be seen among you, nor shall any leaven be seen among you in all your borders.
Notice the reference here to “Egypt” and to “the Canaanites.” This reminds us of the context in which the commandments were given to Israel (in what’s known as The Holiness Code in Leviticus chapters 17 thru 26): “Then the Lord spoke to Moses, saying, “Speak to the sons of Israel and say to them, ‘I am the Lord your God. You shall not do what is done in the land of Egypt where you lived, nor are you to do what is done in the land of Canaan where I am bringing you . . .’” (Leviticus 18:1-3).
So why might this be relevant to remembrance festivals in which the Israelites were not to eat leavened bread? The answer lies in what happens when leaven is added to a plain flour and water dough. The bread maker thoroughly mixes in the leavening agent (in sourdough breadmaking, that is a “starter mixture” of a small amount of fermented dough from previous baking) so that it permeates throughout the dough. The dictionary says this involves “introducing one thing into another so as to affect it throughout” . . . “introducing something that markedly alters the total quality” . . . the “deep implanting of a quality or trait.”
What the Passover meal and the Feast of Unleavened Bread are both symbolically pointing to—what they are “picturing” for Israel and acting out thru their physical participation—is the injunctions in Leviticus 18:1-3; that they are not to introduce any Egyptian or Canaanite “leaven” to the way they live as the people of God. Why are they to be “unleavened”? Because of the way that leaven works. As the Apostle Paul would later say, “A little leaven leavens the whole lump of dough” (Galatians 5:9). Just a small amount of starter mixture will permeate the whole—it will imbue its “qualities” or “traits” through the entire loaf. For better or (in this case) for worse.
The Holiness Code in Leviticus is a collection of commandments headlining behaviors and practices that reflected Egyptian and Canaanite “leaven.” Israel is to be “unleavened” by the values and culture of the Egyptians and the Canaanites—their leaven must not be allowed to imbue the people of God. Israel was to leave behind the leaven of the Egyptians as they made their escape at Passover, and not to allow the leaven of the Canaanites to permeate their lives as they made their home in Canaan. These significant Jewish annual Festivals were to be a perpetual reminder.
In the Old Testament, then, leaven is presented in negative terms. But when it comes to the New Testament, we see Jesus speaking of it in both negative terms and positive terms, on different occasions. Leaven itself is not a problem; it all depends on what the leaven is.
In what’s unsurprisingly called “The Parable of the Leaven,” Jesus says, “To what shall I compare the kingdom of God? It is like leaven, which a woman took and hid in three pecks of flour until it was all leavened.” (Luke 13:20-21; see also, Matthew 13:33). That’s it! A one-sentence parable!
How are we to “read” what he’s saying here? He might be speaking of infusing the kingdom into a secular nation in some way (some would read it as that—a ”christianizing” influence in pagan society) but this seems to cut across Jesus’ statement in John 18:36 that “My kingdom is not of this world.” If we aim to make the world a bit more like the kingdom, firstly we shall fail (there is a fundamental incompatibility between kingdom and world, of which the Jewish festivals’ picturing of “unleavened bread” already warned us) and secondly we shall need to make so many compromises that we will end up with the leaven of the world characterizing the church (because as we’ve seen, “that’s what happens” with leaven, it spreads through everything). As Paul put it in 2 Corinthians 6:8, “Do not be mismatched with unbelievers; for what do righteousness and lawlessness share together, or what does light have in common with darkness?” We also need to be aware that when leaven is working, we don’t see it happening—it does what it does gradually, almost imperceptibly. But pretty soon it’s obvious that the leaven has spread through the whole and there’s no way back.
What, then, might Jesus have had in mind, if it wasn’t some form of Christian nationalism? I think he meant that we should be “leavening” everything we do and how we go about it with kingdom values, kingdom qualities, and kingdom behaviors—that they should be infusing and permeating everything. We should be “carriers” of “the leaven of the kingdom.” This would not just be on a personal, individual level: everything that the church is and does (and how it goes about it) should be leavened with kingdom values, kingdom qualities, and kingdom behaviors, too. If we are in doubt about what “kingdom” looks like, it simply means replicating and propagating Jesus’ values, qualities, and behaviors.
I think this comes into clearer focus when we look at Jesus’ negative references to leaven, where he warns us to beware of the leaven of the Pharisees, the Sadducees, and Herod. (Mark 8:15 and Matthew 16.6; see also Matthew 16:12 and Luke 12.1).
The leaven of Herod, as a puppet king of Israel, installed and kept in power by the Roman legions, represented leadership corrupted by power, prestige, and vested self-interest: a kingdom reflecting secular values but masquerading as the kingdom of the people of God. If ever we are tempted to “protect our position” by compromising kingdom values for self-interest we’re in danger of the leaven of Herod.
What, then, was the leaven of the Pharisees and Sadducees? Jesus tells us in Matthew 16:12 that it was their “teaching.” What primarily distinguished their teaching from Jesus’ teaching was the way they saw Torah—their emphasis on commandments (or more particularly, on how they said they should be interpreted and applied). Jesus’ arguments with Pharisees were generally because he saw what they were doing as weaponizing Scripture against the people God loved—demanding meticulous obedience, with scant regard to the harm done to people in the process.
The big focus of the Pharisees’ teaching was on “holiness”—as they defined it and demanded it of people. They saw “loving the Lord” as synonymous with “loving the law of the Lord,” rather than, as Jesus did, seeing it as synonymous with “loving the people of the Lord” (per Jesus’ reframing of the entire law centered on the Great Commandment). That was their “teaching,” which Jesus saw as unkind and unmerciful.
Many of Jesus’ specific criticisms are in Matthew 23, including that they “tie up heavy burdens and lay them on people’s shoulders;” they “love the place of honor” at events; they have an inordinate love for their roles and their titles (“being called Rabbi by the people”); and they have “neglected the weightier provisions of the Law: justice and mercy and faithfulness.”
If we’re looking to avoid being like the Pharisees, we should not take false comfort from the fact that it was “the law” that they were imposing harshly on people (in other words, we shouldn’t think that they were being legalistic, whereas if it were us doing something similar, we’d just be “honoring Scripture,” or standing firm for “radical kingdom holiness” or some such catchphrase—so “that would be different”). It wouldn’t be. The Pharisees were simply insisting on their equivalents of “the Bible says”—their versions of doctrines, that they were prioritizing over people in the mistaken belief that this was what God most wanted. Weaponizing Scripture is weaponizing Scripture, whether it’s first-century Pharisees doing it or twenty-first-century evangelicals doing it!
How, then, might we sum up the relevance of this for us, in the present? I think it starts with recognizing that we are all “carriers” of leaven—the question is simply what kind of leaven it will be. Will it be genuinely kingdom values, qualities, and practices? Will that be the kind of leaven that infuses and permeates what we do and how we do it? The leaven of the Pharisees is there in the Gospels for us to learn from. It is a warning to us, to be sure that we are not unwittingly replicating it.
It’s a mistake for us to think that the Pharisees were not both committed and sincere. Especially their commitment to “holiness.” But commitment and sincerity are not enough if we’ve misunderstood what God wants, especially insofar as it concerns people. It’s possible to be both sincere and sincerely wrong.