Mishnah Kelim 6:4-7:1

Sugya Map: The Halachic Ontology of the Kira (Stove)

• Core Issue: Defining the minimum structural requirements for a kira to achieve status as a "vessel" (keli) susceptible to tumah.
• Primary Sources: Mishnah Kelim 6:4–7:1.
• Nafka Mina: Whether a structure functions as a vessel (susceptible) or merely a loose collection of materials (immune). Specifically, how "shared" structural components (middle stones/props) divide their status based on utility.

Text Snapshot

"שתי אבנים שעשאן כירה... חציה של זו וחציה של זו של צד הטהורה טהור שמשתמש לטהור וכשניטלו החיצונות חזרו האמצעיות למשפטן הראשון וכולן טמאות." (Rash MiShantz, 6:4)

Nuance: The use of "שמשתמש" (that which serves) implies a functionalist definition of keli. The vessel is not the stone itself, but the utility afforded to the vessel (the pot) resting upon it.

Readings

• Rambam (Commentary on Mishnah): Emphasizes that "plastering with clay" (meruchin b'tit) is the sine qua non of unification. Without the clay, the stones lack the legal identity of a single vessel.
• Rash MiShantz: Highlights the fluidity of tumah. The status of a middle stone is not inherent; it is a mathematical function of its proximity to clean vs. unclean anchors. If the clean anchor is removed, the middle stone's identity shifts entirely to the unclean.

Friction

• Kushya: If the kira is defined by the "support of a pot," why is it susceptible to tumah through its air-space (avir) rather than just contact?
• Terutz: The kira is not just a stand; it is a space-defining entity. Once it reaches the threshold of three fingerbreadths, it creates an "internal" environment, transforming the space under the pot into the functional equivalent of the interior of a vessel.

Intertext

• Mishnah Kelim 10:1: Parallels the measurement of avir (air-space) for ovens. The logic of "three fingerbreadths" acts as the universal heuristic for distinguishing between a "flat surface" and a "contained space."
• SA YD 158: The concept of hibbur (connection) in the context of tumah mirrors the logic here: if two vessels are joined to serve one purpose, they form a single halachic entity.

Psak/Practice

The keli is defined by its toch (interior/utility). In modern meta-psak, this serves as a reminder that the "vessel-ness" of an object is often extrinsic—dependent on how it is positioned and serviced, rather than its raw material composition. If it functions as a unit (plastered/connected), it acquires the law of the unit.

Takeaway

Halachic status often tracks utility: when structural components are shared, their sanctity (or impurity) is partitioned by the function they provide to the neighboring objects.