Mishneh Torah, Sabbath 8

Sugya Map: Defining Derivatives of Plowing (Choresh)

• Issue: Distinguishing the Av Melacha of plowing from its Toldot (derivatives) like weeding (menakesh) and leveling (mishaveh).
• Nafka Mina: Liability hinges on intent (kavana). Does the action serve the earth (plowing) or the plant (sowing)?
• Primary Sources: Shabbat 73b, 103a; Yerushalmi Shabbat 7:2; Mishneh Torah, Sabbath 8:1.

Text Snapshot

"הַמְנַכֵּשׁ בְּעִקְּרֵי הָאִילָנוֹת... כְּדֵי לְיַיֵּף אֶת הַקַּרְקַע הֲרֵי זֶה תּוֹלְדַת חוֹרֵשׁ." (Mishneh Torah, Sabbath 8:1)

Rambam distinguishes between weeding for land-beautification (derivative of plowing) and weeding to aid plant growth (derivative of sowing). The nuance lies in the purpose of the movement of earth: is the ground the object of improvement, or the medium for the plant?

Readings

• Ramban (in Hilchot Kilayim): Suggests that the prohibition of menakesh (weeding) in the context of forbidden mixtures is a Mekayem (maintaining) prohibition—a unique category of active maintenance.
• Yitzchak Yeranen: Argues that menakesh is a derivative of plowing only when the act is non-essential to the plant's survival; if the plant cannot thrive without the action (like pruning), it is classified directly under Zorei'a (sowing/planting).

Friction

Kushya: If menakesh is a derivative of plowing, why does Rambam elsewhere (Hilchot Kilayim 1:2) imply liability for menakesh even when it does not involve moving earth in the traditional sense? Terutz: Rambam’s definition of plowing is functional. Any act that alters the quality of the soil to support growth is "plowing." Thus, "maintaining" the soil composition is the essence of the Melacha, regardless of whether a plowshare is used.

Intertext

• Shabbat 73b: Clarifies that leveling ground inside a house falls under Boneh (building), while outside, it is Choresh.
• SA Orach Chayim 336: Codifies the "perforated flowerpot" (tatzitz nakuv) status, which links the internal/external debate to the status of the earth itself.

Psak/Practice

Meta-Psak: The "intent" heuristic is paramount. If you move earth to clear a path or level a surface, you are bordering on Choresh. If you move earth to clear weeds from a plant, you are bordering on Zorei'a.

Takeaway: Liability for plowing is not about the tool; it is about the state of the soil. Any act that renders the soil more receptive to growth—even by removing an obstacle—is a violation of Choresh.