Ohalos, Chapter 5, Mishnah 7. Our chapter has been occupied with the ability of a keli that is not mekabel tumah to block tumah and to shield what is inside it. Until now the cases were all inside a building: a keli covering an opening in the floor, working together with the ohel so that the tumah of a meis below does not rise to the story above. Our mishnah teaches that this very principle applies outside a building as well, and it brings two cases where a keli leans on the walls of an ohel from without.
The general rule
The mishnah begins with a klal: "Kesheim shematzilin mibifnim, kach matzilin mibachutz" - whatever shielding power keilim that cannot become tamei have indoors, that same power they have outdoors. And the qualification is the familiar one: "im defanos ha'ohalim" - the keli must be operating in concert with an ohel's sides. By itself it accomplishes nothing at all; its entire protective standing comes to it through its partnership with an ohel.
At first hearing this is puzzling. Inside a house the picture is clear: a bor in the ground whose rim rises slightly above the floor, a large basket set over the opening, and the tumah below is held back because the basket is working in partnership with the ohel of the house. But what does it mean to shield from outside a building altogether? For this the mishnah says "keitzad," and gives a case.
The kefishah resting on pegs
"Kefishah shehi nesunah al hayeseidos": before us is a large plaited basket, the sort used for olives, propped up on stakes, on short legs, rather than resting directly on the ground. A kefishah of this kind cannot become tamei, for its capacity is forty se'ah, and wooden keilim that hold that much are beyond the reach of tumah. It is situated outdoors, with one of its sides pressed up to the house's wall.
The Bartenura stresses that it must genuinely be set against that wall. There are two girsaos in his words: according to one, it suffices that the basket stands within a tefach of the wall; according to the other, the word tefach is absent and the basket must be pressed right up against the wall itself.
Now picture a person passing by such a house: he sees a wide round basket on legs, leaning flush against the wall, and wonders what it is doing there. Here is the halachic question. "Vetumah tachteha": there is tumah underneath the basket, and there is room for it, since the basket stands on legs and there is a space beneath it. What is the status of the keilim lying inside the basket?
The halachah is "keilim sheba'kefishah tehorin." Because it abuts the house, the basket acquires the standing of an ohel in itself, borrowing the house's wall to serve as one of its own sides. The basket, for its part, cannot receive tumah. Every requirement is thus satisfied, so even when a meis lies directly below, whatever keilim sit inside the kefishah stay tahor. This is exactly the sort of cooperation between a keli and an ohel's partitions that the mishnah demanded.
Why it must be the wall of a house
But the mishnah is careful about which wall we are speaking of. "Im hayah kosel chatzer o kosel ginah, einah matzlah": if the basket is leaning against the wall of a courtyard or the wall of a garden, it does not shield. Such a wall is not considered an ohel that can combine with the keli, since it carries no roof over it. Without a roof there is nothing here to call a partnership between the keli and the walls of an ohel.
So the very same basket, on the very same legs, with the very same tumah beneath it, yields two opposite results: pressed against the wall of a roofed house, the keilim inside it are tahor; pressed against a courtyard wall or a garden wall, the keilim inside it are tamei.
The beam and the hanging pot
A second case follows: "korah shehi nesunah mikosel lekosel ukedeirah teluyah bah." A beam has been laid across from one wall to the wall opposite, for instance spanning a mavoi between the buildings on either side (that image is simply easier to picture; whether or not it happens to be an alleyway makes no halachic difference). Beams of this sort are familiar from maseches Eruvin. Suspended from the beam is an earthenware pot, its mouth facing up, hanging so close beneath it that it almost, but not quite, makes contact.
"Tumah tachteha": there is tumah beneath the pot. What is the status of keilim lying inside the kedeirah? Here the Tannaim divide.
"Rabbi Akiva metaher": Rabbi Akiva declares those keilim tahor. The beam stretched between the two walls has the status of an ohel, and the pot is near enough to it that we regard it as functioning together with the wall of that ohel.
"VaChachamim metam'in": the Chachamim rule that they are tamei. Since the pot is not actually attached to the ohel and a bit of airspace remains between them, they do not view it as a keli operating in concert with an ohel's sides. For them, nothing short of real contact will suffice.
Defining the dispute
It pays to mark out the limits of this machlokes. Were the pot's mouth genuinely joined to the beam from which it hangs rather than merely dangling beneath it, all would agree that its contents are tahor: such a keli is plainly functioning in partnership with an ohel's sides. And were the pot's mouth a full tefach lower than the beam, all would agree that it shields nothing whatsoever.
The dispute is confined to the intermediate situation, where the pot dangles beneath the korah at a distance of less than a tefach. Rabbi Akiva maintains that even there we may consider the pot annexed to the ohel and treat the two as acting jointly to guard the contents, since any gap smaller than a tefach is regarded as though it were closed off. The Chachamim maintain that no genuine partnership with an ohel's sides exists here; absent an actual join there is no partnership at all, and a keli acting on its own lacks the power to protect what it holds.
Summary
Our mishnah has given us two cases in which the rule that a keli must work together with an ohel operates outside the house rather than inside it.
- A large basket incapable of receiving tumah, propped on stakes with tumah below it: provided it abuts a house, a house in particular, since a house is roofed, the keilim within the basket remain tahor.
- A beam spanning two walls with an earthenware pot hanging from it and tumah below the pot: should the pot's mouth actually touch the beam, all concur that its contents are tahor; should a full tefach intervene, all concur that they are tamei; and where the separation is under a tefach but without contact, Rabbi Akiva rules tahor, since in his view the pot still combines with the beam, while the Chachamim rule tamei, since without a true join the keli stands alone and cannot safeguard what is in it.