Mishneh Torah, Leavened and Unleavened Bread 5-7

Hook

Ever wonder why we go to such wild lengths to avoid bread on Passover, yet eat rice or beans in other cultures? The secret is in the chemistry of "leavening."

Context

• Chametz: Leavened grain products forbidden on Passover.
• The Big Five: Only wheat, spelt, barley, oats, and rye can actually become chametz.
• Kitniyot: Legumes (like rice, beans, lentils). They don't ferment like grain, but some traditions avoid them anyway.
• Mishneh Torah: A clear, organized code of Jewish law written by Maimonides (the Rambam) in the 12th century.

Text Snapshot

"The prohibition against chametz applies only to the five species of grain... However, kitniyot—e.g., rice, millet, beans, lentils and the like—do not become leavened. Even if one kneads rice flour... until it rises like dough that has become leavened, it is permitted to be eaten." — Mishneh Torah, Leavened and Unleavened Bread 5:1

Close Reading

• Leavening vs. Decay: The Rambam explains that when non-grain flours (like rice) "rise," it isn’t the chemical process of leavening (which requires specific enzymes in the "Big Five" grains). It’s just decay. Because it isn't true leavening, it doesn't violate the Torah's restriction.
• The Intent of the Law: The goal isn't just to avoid "fluffy" food. The goal is to avoid the specific fermentation process of the five grains that represent the "bread of slavery" or the "pride" of humanity, replaced by the humble, flat matzah.

Apply It

This week, look at the ingredients of your favorite snacks. Practice identifying the "Big Five" grains. If you see wheat, barley, rye, oats, or spelt, remind yourself: "These are the grains that can become chametz." It takes less than 60 seconds and helps you understand the "why" behind the grocery labels!

Chevruta Mini

1. If the law is only about the five grains, why do you think some communities chose to stop eating kitniyot (rice/beans) too?
2. Does knowing the difference between "leavening" and "decay" make the rules feel more logical or just more complicated to you?

Takeaway

Passover laws aren't random; they focus specifically on the fermentation of the five grains because that is what defines "bread" in Jewish law.