“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). With this parable, Jesus switches the running theme of farming, reaping and sewing and moves us into the kitchen. One phrase that links the previous parable about the mustard seed with this one about yeast is the phrase “that [someone] took and….”. The kingdom of heaven isn’t just a mustard seed but a seed someone took and sewed in his field. The kingdom of heaven isn’t just yeast, it is yeast that a woman took and mixed with flour until all of it was leavened.
The point is that things like bread and trees take time. A seed is necessary for a plant to form; yeast is necessary for bread to rise and neither seed nor yeast are ends in themselves. They are catalysts, you might say, for growth and Jesus’ parables highlight this in the way He tells them: the purpose of all that growth from the mustard seed is a home for many birds; the point of adding yeast is so that the flour will rise. Seeds have to be sewn for plants to come of them; otherwise they die without anything to show for their existence. Yeast remains inert until worked into flour even as the dough will remain low and flat apart from yeast. So Jesus is saying that apart from the kingdom of God, nothing rises but also that apart from us, apart from the hearts, souls, wills, strengths, bodies and minds of the children of God, the kingdom of God remains ineffectual as well.
Don’t miss this point, now. Yeast is what makes bread dough rise but it itself does not rise alone. Yeast reacts with sugars and produces carbon dioxide, leavening whatever flour it is put with but if it is never mixed into dough, it will remain just as unleavened as yeast-free dough. The kingdom of heaven is the yeast, we are the flour – both are needed, though it is clear that the kingdom, not the dough, is the catalyst for bread. In the case where the kingdom of heaven is the seed, we saw that a seed has all it needs to grow except for one thing; the same goes for bread. So, the kingdom of heaven is an agent of growth, and it needs something in which or someone in whom to grow.
A few years ago, I found out by blood test that I’m actually allergic to (baker’s and brewer’s) yeast. What this means, essentially, is that my system is very sensitive to an overgrowth of it, reacting with red rashes, a clogged nose and head/stomach aches. Yeast allergies are more common that we realize – they are often misdiagnosed as wheat allergies in the absence of blood work and thus go untreated – though not inert – for far too long. Because of this allergy, I’ve found that yeast is actually everywhere, not just breads (and alcohol) – it’s in fermented foods (sauerkraut, pickles, vinegar, etc.), anything processed, anything aged and most snack flavorings (like Sour Cream and Onion Potato Chips).
In terms of food allergies, ubiquity and rapid multiplication are not desirable qualities but I so long for these for the kingdom of heaven. The fact that yeast can be found everywhere (I’m literally allergic to anything if you leave it in the fridge long enough as part of the aging process is yeast growth) and flowers quickly makes Jesus’ comparison of the kingdom of heaven to yeast all the more powerful. The kingdom of heaven will not one day be everywhere, it already is. And the kingdom of heaven will not in the future multiply, it is doing so now. Sometimes, it’s just that huge things start out so very small.