Mishneh Torah, Sabbath 10

Sugya Map

The sugya of Koshair (Tying) and its dialectical counterparts, Matir (Untying) and Kore’a (Tearing), revolves around the definition of "constructive" labor on Shabbat. The Rambam centers the prohibition on the intersection of two conditions: intent of permanence (kashar shel kayama) and professional mastery (ma’aseh uman).

• Core Issue: Does the prohibition of Koshair apply to any knot intended to last, or only to those executed with specialized expertise?
• Nafka Mina: The status of a common knot (e.g., a simple shoelace knot) tied with the intent of permanence. If one follows the Rambam, it is permitted (or at most, shvut); if one follows Rashi/Rabbenu Asher, it is a Chayav violation.
• Primary Sources:
  • Shabbat 111b–113a (Talmudic foundations).
  • Mishneh Torah, Hilchot Shabbat 10:1–10:11.
  • Shulchan Aruch, Orach Chayim 317:1.

Text Snapshot

MT, Shabbat 10:1:

"קֶשֶׁר שֶׁל קַיָּמָה וְהוּא מַעֲשֵׂה אֻמָּן חַיָּב." (A knot that is permanent and is the work of a craftsman is liable.)

Nuance: The Rambam uses ma’aseh uman (the work of a craftsman) as a gezeirat hakatuv or a strict definition of the melacha. Note the dikduk: the Rambam does not say "a knot that is a craftsman's work," but "a knot that is [of the category of] ma’aseh uman." The Steinsaltz nuance captures this: kashar shel kayama is kavu’a—a state of permanence—while ma’aseh uman serves as the objective measure of the knot's complexity.

Readings

1. The Rambam’s Intellectual Architecture

The Rambam’s approach here is rigorously functionalist. For the Rambam, the prohibition of Koshair is defined by the Mishkan. The fishermen (chilazon gatherers) tied nets with complex, professional knots meant to hold against the sea's resistance. Consequently, the Rambam limits Koshair to knots requiring professional skill. In Hilchot Shabbat 10:1, he explicitly excludes non-professional knots from Torah liability. His chiddush is the radical separation of intent from the mechanical nature of the knot: even if one intends for a knot to last forever, if it is a "simple" knot (e.g., a shoelace), it lacks the umanut (craftsmanship) required to be Chayav.

2. The Rashi/Rosh Opposition

Conversely, Rashi and the Rosh (quoted in the footnotes of the provided text) pivot away from the umanut requirement. For them, Koshair is defined by kayama (permanence). If a knot is strong enough to last, the intent of the tier makes it a melacha. Their chiddush is that the "craftsman" mentioned in the Talmud is merely an example of a knot that happens to be permanent, not a sine qua non for the prohibition. This creates a much broader net of liability, encompassing domestic knots that the Rambam would deem permitted. The Ramah (OC 317:1) adopts this stricter view, fundamentally diverging from the Shulchan Aruch’s adoption of the Rambam.

Friction

The Kushya: The "Destroyer" Paradox

The strongest kushya against the Rambam arises from the laws of Kore’a (Tearing). The Rambam maintains that Kore’a is only a melacha if it is done to "sew two stitches" (Kore’a al menat litfor). Yet, he includes the kore’a done in chamato (fit of rage) or for the dead as Chayav.

The Conflict: If the Rambam is a strict adherent of melacha she’eina tzricha legufah (liability even without constructive intent), why does he emphasize the "settling of the mind" (mishayev et da’ato) as the justification for liability in kore’a? Is this not an admission that the intent of the actor defines the nature of the labor?

The Terutz: The Internalized Construction

The Ohr Sameach (10:10:1) resolves this by noting that the Rambam follows Rabbi Yehudah regarding melacha she’eina tzricha legufah. The "settling of the mind" is not merely psychological; it is an objective tikkun (fix) for the person. Just as one builds a wall, one "builds" their own emotional state. Thus, the kore’a in anger is constructive because the result (the alleviation of inner tension) is a positive output. The Rambam isn't ignoring the melacha definition; he is expanding the definition of "constructive output" to include the internal human state, provided it is a kiddush of the actor’s intent.

Intertext

1. Tanakh: The imagery of the "craftsman" (uman) in 1 Chronicles 22:15, where David prepares "craftsmen" for the construction of the Temple, serves as the meta-textual archetype for the Rambam’s ma’aseh uman. The Temple was the locus of melacha, so the "craftsman" is the agent of melacha.
2. Shulchan Aruch: In Orach Chayim 317, the tension between the Rambam (pro-permanence + pro-skill) and the Ramah (pro-permanence regardless of skill) is the primary engine of the halachot of knots. The Mishnah Berurah 317:29 further mediates this by allowing loops (aniva) as a workaround, effectively navigating the "permanence" constraint by ensuring the knot remains technically temporary.

Psak/Practice

In contemporary psak, the Rambam’s heuristic remains the bedrock of Ashkenazi and Sephardi practice regarding "modern" knots (e.g., zip ties, double knots).

• The Heuristic: If a knot is both "permanent" and "professional/complex," it is forbidden.
• The Meta-Psak: The Magen Avraham (317:8) and Mishnah Berurah often act as the "fail-safe" for the Rambam’s leniencies. Even if the Rambam permits a simple knot, the Minhag (practice) is to avoid it if it appears "permanent."
• Application: When tying a shoe, a single knot is generally permitted (not uman), but if one double-knots it with the intent of leaving it, the Ramah would forbid it, and the Acharonim advise against it to satisfy all shittot.

Takeaway

The Rambam’s law of Koshair is a study in objective criteria; he refuses to let the subjective intent of the user override the objective technicality of the act. We learn that Shabbat is not about what we feel we are doing, but about the category of impact we leave upon the material world.