HALAKHAH · SHABBAT · 3 OF 6
Understanding melakhah
The thirty-nine categories are the beginning of a way to understand actions, not a list of thirty-nine isolated tasks. Learn how our sources group activities and explain their relationships.
In this lesson
From a list to a way of learning
In Shabbat: remember and keep, we learned that melakhah, the work prohibited on Shabbat, is not defined simply by tiredness or payment. Now we will ask a more precise question: how can different activities belong to the same category?
Halakhah is Jewish law as it guides our actions. The Mishnah, a collection of our sages’ teachings, names the principal categories of melakhah. Rambam, Rabbi Moshe ben Maimon, explains their relationships in his later code of Jewish law, the Mishneh Torah. Despite their similar names, the Mishnah and Mishneh Torah are different works.
We will follow the classifications these sources actually give. That will teach us both how to explain an example and how to ask a better question when an unfamiliar activity needs further study.
What does thirty-nine count?
Shabbat 7:2 means tractate Shabbat, chapter 7, mishnah 2. A tractate is a named book within the Mishnah. Here is the heading and the start of its list:
אבות מלאכות ארבעים חסר אחת: החורש, והזורע, והקוצר
The principal categories of melakhah are forty less one: plowing, sowing and reaping.
English rendering by Messianic Yeshiva
Av literally means “father”; here it means a principal category. Avot is its plural. Melakhot is the plural of melakhah. So avot melakhot names the principal categories, not a list of jobs or professions.
Plowing turns or breaks soil for cultivation. Sowing puts in seed. Reaping cuts or harvests a growing crop. The full list reaches beyond the field to such activities as writing two letters, building and kindling. Its entries identify kinds of activity, sometimes with a stated measure or purpose.
1. Why is “exactly thirty-nine separate actions” a weak reading of the heading?
The heading counts thirty-nine principal categories. It does not say that only thirty-nine individual movements or named tasks can belong to them. We still need to learn what each category includes.
Nor does the count tell us which action takes the most effort. It organizes kinds of melakhah, not degrees of tiredness.
Different verbs, one principal category
Rambam follows his own list of the thirty-nine categories with an explanation. A trench is a long, narrow channel dug in the ground.
כל אלו המלאכות וכל שהוא מעניינן, הן הנקראין אבות מלאכות. כיצד הוא עניינן: אחד החורש, או החופר, או העושה חריץ--הרי זה אב מלאכה: שכל אחת ואחת מהן חפירה בקרקע, ועניין אחד הוא.
All these melakhot, and whatever is of their kind, are called principal categories of melakhah. What does “of their kind” mean? Whether one plows, digs or makes a trench, this is a principal category of melakhah: each is digging in the ground, and they are one kind.
English rendering by Messianic Yeshiva
A worked comparison
- Notice the actions. Plowing, digging and making a trench have different ordinary names.
- Find the shared feature. Rambam identifies each as digging in the ground.
- Keep his classification. He puts them within one principal category. A different everyday verb does not, by itself, make a new av.
This is more precise than saying “they all involve effort” or “they all use tools.” Those descriptions could cover many unrelated activities. Rambam names the feature relevant to this grouping.
2. Repair this claim: “Digging is a different word from plowing, so it must be a different principal category.”
“Rambam places plowing, digging and making a trench within one av because each is digging in the ground.” The source gives both the grouping and its reason.
Do not repair the claim by automatically calling digging a derived category instead. In this paragraph, Rambam includes it within the principal category itself.
What is a derived category?
Rambam also distinguishes a toladah, a derived category; the plural is toladot. Its relationship to an av matters, but it is not simply another name for every additional example.
התולדה, היא המלאכה הדומה לאב מאלו האבות.
A derived category is a melakhah resembling one of these principal categories.
English rendering by Messianic Yeshiva
In the explanation that follows, Rambam describes grinding as taking one body and dividing it into many smaller bodies. At the end of that paragraph, he gives this example. A goldsmith works precious metal; filing rubs material away with a rough tool.
וכן הלוקח לשון של מתכת, ושף אותו כדי ליקח מעפרו כדרך שעושים צורפי הזהב--הרי זה תולדת טחינה.
Likewise, one who takes a bar of metal and files it to obtain some of its powder, as goldsmiths do: this is a derived category of grinding.
English rendering by Messianic Yeshiva
Here the result matters: a solid piece is reduced to particles that the worker wants. Rambam connects this metalworking example to grinding. He does not classify it merely by how long the work takes or by the fact that someone is working with metal.
3. Why must a careful summary keep “to obtain some of its powder”?
That purpose helps explain the resemblance to grinding: the worker is producing small particles from a solid body. Removing it would turn Rambam’s specific example into the much broader claim “all work on metal is grinding.” The source has not said that.
In 7:7, Rambam treats both an av and a toladah as Torah-level prohibitions. “Derived” describes a relationship between categories; it does not mean an optional custom or merely a rabbinic caution. His later discussion distinguishes how categories are counted in certain cases, not whether their observance matters.
4. Which source corrects “A toladah is only a custom,” and which source gives the thirty-nine-category heading?
Rambam’s code, especially 7:7, supplies the correction: both principal and derived categories carry Torah-level prohibition. The heading we read comes from Mishnah Shabbat 7:2.
The Mishnah’s list and Rambam’s explanatory cases belong together in our learning, but they are not quotations from the same work.
Make a new comparison
Now read another paragraph from Rambam. Legumes are crops such as beans and peas. Before opening the answer, compare reaping grain and picking figs here with filing metal to obtain powder above.
וכן אחד הקוצר תבואה או קטנית, או הבוצר ענבים, או הגודר תמרים, או המוסק זיתים, או האורה תאנים--כל אלו אב מלאכה אחת הן: שכל אחת מהן לעקור דבר מגידוליו מתכוון. ועל דרך זו, שאר האבות.
Likewise, whether one reaps grain or legumes, harvests grapes, gathers dates, picks olives or picks figs, all these are one principal category of melakhah: in each, one intends to detach something from where it grows. The other principal categories follow this pattern.
English rendering by Messianic Yeshiva
Give two sentences. In the first, name the grouping and reason for grain and figs. In the second, name the grouping and reason for the metal example. Your comparison needs more than “all three are work.”
5. How do the two relationships differ?
“Rambam places reaping grain and picking figs within one av: each detaches something from where it grows. He calls filing metal to obtain powder a toladah of grinding: its particle-making resembles the dividing process he explains in 7:5.”
The first pair shows different activities within a principal category. The second shows a derived category related to an av. Different materials or different everyday verbs do not automatically settle which relationship a source gives.
A learner draws this conclusion: “Whenever two actions look similar, I can give them the same classification.” Test that conclusion against the way we actually worked.
6. What did our comparisons establish, and what did they not establish?
They established the groupings Rambam gives and the reasons he states for them. We attended to the action, its object and its intended result.
They did not turn any resemblance we notice into a rule. We learned the categories through the source, rather than deciding from appearances alone. A new practical case calls for its own relevant teaching and details.
Return to the reasons
Close the source cards. Explain av and toladah aloud. Give one example of different activities within one av and one example of a toladah, including each source’s reason. Then name the two different works we read.
8. Check your explanation
An av is a principal category; a toladah is a derived category resembling an av. Plowing, digging and making a trench share Rambam’s feature of digging in the ground. His harvesting examples share detaching something from where it grows. Filing metal to obtain powder is his example of a toladah of grinding.
We read the Mishnah and Rambam’s later Mishneh Torah. Both principal and derived categories matter at the Torah level. If you remembered only a category name, reopen the relevant paragraph and recover its reason.
Read in context
- Mishnah Shabbat 7:2: the complete list of thirty-nine principal categories. Our source card selects only its opening and first three entries.
- Rambam, Laws of Shabbat 7:2, 4–5 and 7: activities within an av, the harvesting comparison, the definition and examples of toladot, and their Torah-level status. We read complete paragraphs 2 and 4, with selected sentences from paragraph 5.