Ohalos, Chapter 12, Mishnah 8. Our mishnah continues the chapter's investigation of tumas meis and the parts of a building that stand at its edges. Here the focus is the doorway itself: the threshold beneath the entrance and the beam above it. When a kezayis min hameis rests on one of these, do we treat that spot as belonging to the house, so that the house becomes tomei, or as standing outside it?
Two terms need to be clear before we begin. The iskufa is the threshold, the low block or step at the entrance that one steps over on the way in. It runs from one doorpost to the other and typically juts out somewhat toward the street, beyond the line of the doorway. The mashkof is the lintel, the beam that lies across the top of the doorframe, and it too usually projects a bit outward, past the doorposts.
Tumah attached to the projecting section of the threshold
"Kezayis min hameis mudbak la'iskufa": a kezayis of a meis is attached to the threshold. The mishnah is speaking of the portion of the iskufa that extends outward, and not merely outward but so far out that if one were to draw a vertical line straight up from the tumah, that line would rise past the edge of the mashkof and into the open sky, with no beam above it at all.
The mishnah records the machlokes. "Rebbi Eliezer metameh es habayis": according to Rebbi Eliezer, the interior contracts tumah. He regards the iskufa as a full component of the dwelling, so wherever tumah settles upon it, including that outward stretch lying past the edge of the lintel, it counts as tumah within the dwelling.
"Rebbi Yehoshua metaher." Rebbi Yehoshua holds otherwise. To his mind, whatever length of threshold extends beyond the mashkof has no share in the dwelling, and a kezayis resting there leaves the inside tohor. The Bartenura rules that the halachah follows Rebbi Yehoshua.
Tumah underneath the threshold
The mishnah goes on: "hayah nasun tachas ha'iskufa," if the kezayis was set beneath the threshold, once again beneath the section that juts outward, then "yidonu mechtza lemechtza," the ruling turns on a halving. We take the length of iskufa protruding from the building and mark its midpoint. Tumah below the inner half conveys tumah to the interior; tumah below the outer half leaves the interior tohor.
Here the two Tannaim do not argue. The Tiferes Yisroel explains that Rebbi Eliezer counts the iskufa as an arm of the dwelling only where the tumah lies exposed on top of it. Once the tumah is concealed below, all opinions agree that the protruding length is divided at its midpoint.
This is essentially the same principle we encountered back in Perek Vov concerning the thickness of a wall: tumah lodged within the wall is attributed to whichever side of the midpoint it occupies, inward or outward. The threshold is judged by that identical logic.
A kezayis stuck to the lintel
The mishnah turns to the beam: "mudbak lamashkof," the kezayis min hameis adheres to the lower face of the lintel, on the length of beam that overhangs outward, standing in front of the doorposts rather than spanning the gap between them. Nevertheless, "habayis tomei": the dwelling contracts tumah, for anything positioned under the mashkof carries the status of being inside.
Here again Rebbi Eliezer and Rebbi Yehoshua are in agreement; Rebbi Yehoshua concedes that the space under the beam belongs to the house. The one who differs is Rebbi Yosi. "Rebbi Yosi metaher": in his opinion, the portion of the mashkof that stands out in front of the doorway is not reckoned as part of the house, and the house stays tohor.
When the kezayis lies within the dwelling
Until now the question was whether tumah situated outside the house penetrates inward. The mishnah now reverses the picture: "hayah nasun besoch habayis," the kezayis min hameis is lying inside the house. What is the status of a person standing outside who touches the doorway?
"Hanogeia bamashkof tomei." Whoever touches the lintel contracts tumah, since the mashkof in its entirety is reckoned with the dwelling; such contact amounts, in some measure, to having entered the ohel hameis. Apparently even Rebbi Yosi would accept this halachah.
"Hanogeia ba'iskufa": now the person lays his hand on the projecting length of threshold, at a spot where a glance upward reveals neither beam nor roof but only open sky. "Rebbi Eliezer metameh." True to his approach throughout, Rebbi Eliezer reckons the iskufa in its entirety with the dwelling: just as a kezayis placed there conveys tumah inward, so a person making contact with it while a kezayis lies within contracts tumah.
"Rebbi Yehoshua omer": the answer turns on the exact spot touched. "Mitefach ulematah tahor," contact with the flank of the threshold at any point below its highest tefach leaves him tohor, and the Bartenura explains that such contact is no different from touching the ground. "Mitefach ulema'alah tamei," contact anywhere within that uppermost tefach of the flank, and all the more so with the top surface, renders him tomei, because that measure alone is reckoned with the dwelling.
The Bartenura's question
The Bartenura points out a plain difficulty. At the opening of the mishnah Rebbi Yehoshua held that a kezayis fastened to the projecting stretch of iskufa leaves the interior tohor, which shows that he does not reckon that stretch with the dwelling. Why, then, once the kezayis lies within, does he say that contact with the iskufa in its top tefach conveys tumah?
He answers that when the tumah is inside we are stricter, a pattern we have met repeatedly: the nature of tumah is to travel outward, not inward. Tumah does not remain shut inside a house; it presses toward the exit, and the route by which it departs is thereby rendered tomei. So tumah standing outside does not push its way in, but tumah trapped inside must leave, and the threshold lies along its path.
Review of the cases
- A kezayis min hameis fastened to the projecting stretch of iskufa, past the edge of the mashkof: Rebbi Eliezer reckons the whole threshold with the dwelling and declares the interior tomei; Rebbi Yehoshua holds that the outward stretch has no share in the dwelling, leaving the inside tohor. (Whether the mishnah insists that the kezayis actually adhere there rather than simply lie upon it is a point taken up by the Mishnah Achronah, and it repays study.)
- The kezayis below the iskufa: all opinions divide the protruding length at its midpoint. Beneath the outer half, the interior is tohor; beneath the inner half, it is tomei.
- The kezayis stuck to the underside of the mashkof, on the length overhanging in front of the doorposts: for Rebbi Eliezer and Rebbi Yehoshua the dwelling contracts tumah; Rebbi Yosi maintains that this overhang has no share in the dwelling, and the interior stays tohor.
- The kezayis within the dwelling and a person makes contact with the mashkof, even with its outer overhang: he contracts tumah.
- The kezayis within the dwelling and a person makes contact with the iskufa: Rebbi Eliezer, true to his approach that the threshold is reckoned with the dwelling, declares him tomei; Rebbi Yehoshua rules by the spot touched, tohor beneath the highest tefach and tomei within it.
And the reason Rebbi Yehoshua is stricter when the tumah sits inside than when it sits outside is the principle that closes the mishnah for us: tumah in a house must make its way out, and wherever tumah is on its way out, we rule more stringently.