He told them another parable: “The kingdom of heaven is like yeast that a woman took and mixed in with three measures of flour until all of it was leavened.”
Matthew 13:33 (NRSV)
If I had a little more foresight, I probably would have just tacked this on to the end of the parable of the mustard seed. The overall point is basically the same. The kingdom of heaven starts as a small introduction into a much larger entity, and before you know it, it’s grown throughout.
Where things differ somewhat is in the precedent for the imagery. With the growing tree, we saw how this was a metaphor used in the Old Testament to describe the rise of powerful rulers and their kingdoms, not the least of which being an image of the restoration of Israel after other trees have been cut down.
By contrast, there’s no consistent use of the imagery for yeast.
There is a fair amount of yeast imagery depicting the spread of sin and corruption in the world. We see this in both Jesus and Paul’s use of the image (Matthew 16:6, 1 Corinthians 5:6-8, Galatians 5:9). The fast-spreading properties of leaven are used negatively, here.
Of special note is the Matthew 16:6 passage, because Jesus explains that the leaven is the “teaching” of the Pharisees. In other words, it’s not the intrinsic, sinful desires of the Pharisees Jesus warns about, but rather the teaching of the Pharisees. This comes after another episode where the Pharisees try to trap Jesus by asking for a sign. The Pharisees are a force in the world that is destructive to Jesus and his disciples.
In the Talmud, yeast is used as a metaphor for the spread of sin and evil a few times, but perhaps the most illuminating is the prayer of Rabbi Alexandri as we read in Berachos 17b:
Rabbi Alexandri, when he finished his daily prayer, said the following: ‘Master of the Universe, it is revealed and known to You that our true desire is to do Your will. What prevents it but the “yeast in the dough” and the subjugation of the exile! May it be Your will, O Lord, to deliver us from their hands, and we shall return to perform the decrees of our will with a perfect heart.’
In this prayer, the image of yeast in the dough is paired with “the subjugation of the exile.” Foreign dominion created an environment that permeated the Jewish people, turning their hearts from doing the Lord’s will. In the prayer, we see R. Alexandri asking for political deliverance that will result in a changed heart and a return to faithfulness.
Also, unleavened bread is a key feature of the Passover story as well as the laws commanding future observance of the Passover. Absolutely no leaven is to be used. In the story, this is because the Israelites have to leave that very night. There is no time to make leavened bread, so the unleavened bread is a marker of the haste with which God will deliver them from Egypt.
However, this also takes on an ethical significance. Passover observance requires, not only the use of unleavened bread, but the complete purging of leaven from the house. A Sephardic prayer that follows the burning of the gathered leaven ends with, “Just as we did remove chametz from our homes and burned it, so we pray that we should be able to remove evil inclinations from within us always.”
Leaven, however, also has positive implications. Leavened bread is used in peace offerings and wave offerings as commanded in Leviticus. One particularly interesting reference to this practice is in Amos 4:
Hear this word, you cows of Bashan
who are on Mount Samaria,
who oppress the poor, who crush the needy,
who say to their husbands, “Bring something to drink!”
The Lord God has sworn by his holiness:
The time is surely coming upon you,
when they shall take you away with hooks,
even the last of you with fishhooks.
Through breaches in the wall you shall leave,
each one straight ahead;
and you shall be flung out into Harmon,
says the Lord.
Come to Bethel—and transgress;
to Gilgal—and multiply transgression;
bring your sacrifices every morning,
your tithes every three days;
bring a thank offering of leavened bread,
and proclaim freewill offerings, publish them;
for so you love to do, O people of Israel!
says the Lord God.
Amos 4:1-5 (NRSV)
In a common type of prophetic warning, Amos points out that Israel observes the Torah laws for worship (sacrifices, tithes, offerings), but this display only makes God angrier because they oppress the poor and the needy. Interestingly, for Matthew’s purposes, this is followed by a long list of things God had done (punishments) before Israel, yet they did not repent.
Are any or all of these facets behind Jesus’ parable? With the mustard seed, the imagery very strongly recalled the idea of oppressors being cast down so Israel could be exalted. Does his use of leaven recall, like R. Alexandri’s prayer, deliverance from an oppressor so that Israel would return to faithful service? Does it recall the warnings and promise of Amos, that the leaven of true faithfulness would be a condemnation against a corrupt Israel who would not repent despite what God was doing in their midst?
Did he just pick leaven because it spreads fast and takes over?
Jesus does not tell us, and unlike the parable of the mustard seed, his language can’t be closely mapped to Old Testament usage.
The one thing we can say with some confidence is that, like the parable of the mustard seed, the focus is clearly on something that begins as small and insignificant, yet grows to spread throughout the whole shebang. Just as a little yeast leavens all the flour, even though there is much more flour than yeast at the beginning, so, too, will the kingdom of God fill the world, despite its apparent size at the beginning.
A hopeful teaching that would be important to would-be Jesus followers at this point in Matthew. It would be easy to get discouraged at the lack of response. Jesus does not tell them that the numbers don’t matter, nor does he talk about quality over quantity. His declaration is that this tiny bundle of faithful Israel will grow and spread throughout the known world – Abraham’s promise renewed.
- Did early church history bear out Jesus’ analogy? How did such a small, insignificant movement in a backwater Roman province end up swallowing empires? What were the actual historical mechanisms by which this happened?
- In our contemporary world, we generally think of the “spread” of Christianity as sending people with a message to tell people who have not heard it. This was certainly part of how the kingdom spread in the early church. Was it the only part? What can we observe in those early centuries of church growth that have an analogy, now?