Ohalos, Chapter 14, Mishnah 4. This chapter has been occupied with the ziz, the ledge or overhang that projects from a wall and functions as an ohel to carry tumah. Some of the earlier cases dealt with a simple rod resting on pegs; here we return to a genuine overhang, one that is built into the structure of the house itself.
The Mishnah's first words describe a ledge that wraps around the outside of a building: "Ziz shehu sovev," a ziz that runs around, "es kol habayis," the whole house. Think of a decorative band of stone a tefach wide, set into the wall and continuing along it. Look at the building from either flank and the ledge is there; walk around to the rear and it is there too. The one place where it is not complete is the front: it fails to reach across the whole facade from corner to corner.
Now position yourself facing the front, with the entrance straight ahead. Coming around from the wall on your left, the ledge turns the corner onto the facade and then breaks off before it arrives anywhere near the opening. From the wall on your right, the ledge likewise turns onto the facade, but this side does not break off. It carries on for a bit beyond the edge of the entrance: "va'ochel bapessach shalosh etzba'os," it "eats" three fingerbreadths of the doorway. No eating is taking place, naturally. The expression tells us that the ledge juts across the opening and covers three etzba'os of its width. The Bartenura points out that above the rest of that opening there is nothing at all.
Had the ziz projected a full tefach across the doorway, every opinion would agree that the entire arrangement is tamei. The whole question of this Mishnah arises precisely because the overlap is only three etzba'os, less than the standard shiur, and so the halachah is not obvious.
Tumah inside the house
The first ruling: "Tumah babayis, keilim shetachtov temeiyim," if the tumah is inside the house, keilim positioned beneath the overhang are tamei. Anywhere beneath it, all the way around the building. The reason is that the tumah rises from within the house and reaches the underside of that segment of ziz which projects over the doorway. Even though that segment does not measure a tefach by a tefach, the tumah nevertheless takes hold there, and once it has taken hold it travels onward along the entire circuit of the ziz. A keli resting beneath the ziz at the back of the house becomes tamei.
The meforshim explain that we are really dealing with two distinct ohalim here. The house is one ohel. The ziz, which the Mishnah assumes projects a tefach out from the wall and is a tefach wide, is an ohel in its own right. The only deficiency is that the portion of it standing over the doorway does not amount to a tefach by a tefach. Even so, when tumah is in the house, whatever lies under the ziz becomes tamei, and in this there is no dispute whatsoever. This follows a pattern we have met repeatedly: when tumah is inside a house, we rule stringently regarding the route by which it emerges, because the tumah must find its way out.
Tumah beneath the ziz
Tumah beneath the ziz
The Mishnah now turns the case around: "Tumah tachtov," the tumah is outdoors, lying under the overhang. On this the Tanna'im part ways. Rebbi Eliezer holds "metamei es habayis," that keilim inside are rendered tamei, for the tumah spreads beneath the ledge and from there makes its way indoors. Rebbi Yehoshua is "metaher," ruling that whatever is in the house stays tahor. His reasoning: above the entrance this overhang lacks the square tefach it would need. Granted, it is a tefach in how far it protrudes, but measured along the opening it comes to only three etzba'os, so the tumah has no passage through which to move inward. Rebbi Yehoshua concedes entirely that tumah situated indoors emerges and spreads under the ledge; what he denies is the journey in the opposite direction.
The aksadra around a courtyard
The aksadra around a courtyard
"Vechen bechatzer shehu mukefes aksadra," and the identical law governs a courtyard ringed by an aksadra. Stand in the middle of such a courtyard. Along the wall to your right stands a line of posts with a platform laid over them; along the wall to your left, the same. Straight ahead of you is the doorway of the house. Where the platform reaches the facade, it turns the corner and continues for a short stretch across it, precisely as the ledge did in the opening case. The platform coming from your left turns and terminates before the doorway, so that nothing of it lies above the entrance on that side. The platform coming from your right turns and does not terminate early: it reaches three fingerbreadths over the entrance and ends there. Above the middle of the entrance there is nothing.
The ruling here matches the ruling there, and so does the disagreement. When the tumah is indoors, keilim lying under the platform are tamei, and no one contests it. When the tumah is under the platform, Rebbi Eliezer holds that keilim within the house become tamei, whereas Rebbi Yehoshua maintains that although tumah exits the house and spreads beneath the platform, the reverse route, inward from beneath it, is closed off.
The root of the dispute
The root of the dispute
What lies behind the argument? Think back to how the perek began: a ziz "meivi es hatumah," it conveys tumah, "kol shehu," no matter how small it is, even without a full tefach of projection from the wall. What the two Tanna'im are debating is precisely how far that leniency of "kol shehu" reaches.
In Rebbi Eliezer's reading, both dimensions are included. The ledge need not protrude a handbreadth from the face of the wall, and neither must it stretch a handbreadth along the opening. "Kol shehu" means that no measurement is demanded here at all; the smallest bit will do.
Rebbi Yehoshua reads it more narrowly. "Kol shehu" speaks of the width, the extent to which the ziz juts out from the wall. Look down at the ziz from the roof and it need not measure a tefach across. But in its length over the doorway a tefach is required, and in our case that requirement is not met.
The dispute, then, hangs entirely on how one construes the Mishnah that opened the perek. With tumah indoors, both Tanna'im are strict, since tumah shut inside a house has to find an exit. With the tumah outside under the ledge, and without a tefach of length above the entrance, Rebbi Eliezer says the tumah gets in, because to his mind no such length is required, while Rebbi Yehoshua says it does not, because he insists on that measurement. The same applies to both cases of the Mishnah, the ledge circling the house and the aksadra, that platform on posts reaching less than a handbreadth over the doorway: for Rebbi Eliezer tumah beneath it penetrates the house, and Rebbi Yehoshua rules tahor.