One-Page Learn · The Halachos at a glance
מְטַמְּאֵי מִשְׁכָּב וּמוֹשָׁב
Those Who Render Couch and Seat Impure 7-9
Sefer Taharah · The five ways of being held up by a thing without ever touching it, the one impurity in the Torah that travels by moving rather than by contact, and the exact line between a man's own force and the trembling of the room
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Ways a zav renders a bed or a seat impure, and not one of them is touching
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Ways such a surface then conveys impurity back to a person
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Cloths under a bed's legs, all impure; under an animal's feet, all pure
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Sheet of paper between an impure midras and food leaves the food pure
Ch 7Five postures, and the majority of a body
- Midras is support, not contact. A zav renders a surface made for lying, sitting or riding impure in five ways, by standing above it, sitting above it, lying on it, hanging from it or leaning on it, and a stone in between changes nothing, since being carried by it in any way makes it a primary source of impurity; these five together are what the word midras means wherever it appears. (7:1)
- And seven ways back. Such a surface conveys impurity to a person in those same five ways plus touching and carrying, and the verse about one who sits where the zav had sat is read as speaking of the place rather than the object, so a pure man who sits there is impure even with a stone between, and he defiles his garments as long as he has not separated from it. (7:2)
- Nothing counts until most of the body rests on it. Neither the zav nor a pure man on an impure midras is affected unless the majority of the body is supported, so five benches end to end are all impure and the same five side by side are all pure, unless he slept on them and may have turned; of six supports holding two hands, two feet, the head and the trunk, only the one under the trunk is impure. (7:3, 7:4)
- A bed cannot spare a leg and an animal can. Four surfaces under the four legs of a bed a zav sits on are all impure, since the bed cannot stand on three, while four surfaces under the four feet of an animal he rides are all pure, since the animal can stand on three and each foot may be a mere assist, and an assist is not significant. (7:5, 7:6)
- Stand up and let us get on with our work. An article not made for sitting stays pure when he sits on it, since he can be told to rise so the article can do its own job, so a kneading trough turned over, a curtain and a ship's sail are pure while a cloak, a veil, a drinking pouch and a carrying bag do contract midras; whether his weight actually rests on what lies beneath decides the keilim under an olive press and the garments under a launderer's press. (7:7, 7:8)
RememberThe question is never who touched what. It is what was actually bearing the majority of his weight.
Ch 8Heseit, the reach that has no comparison
- The one impurity that works by moving. Everywhere else a person who moves a source of impurity is impure and a person moved by one is not, but a zav who moves a pure person or a pure vessel makes it impure as though he had touched it, and the Rambam calls this an extra dimension of impurity with no comparison in the entire Torah; the same applies to a zavah, a niddah and a woman after childbirth. (8:1, 8:2)
- Moving reaches further than touching. A sealed earthenware container touched by a zav stays pure and the same container moved by him is impure, as is a hollow vessel with no opening, a needle wholly embedded in wood or a ring embedded in a brick when he lifts what encloses them; a zav who puts his hand inside an earthenware container without touching or moving it leaves it pure. (8:3, 8:4)
- Revealed limbs move, hidden ones carry. A zav who moves a person or a vessel with a rod held fast in the folds of his skin leaves it pure, since the verse likens moving to touching and touching is done with revealed parts of the body, while a pure man who moves a zav with a rod held in his own skin folds is impure, since moving an impure thing is a form of carrying and hidden parts of the body do carry. (8:5)
- The balance scale. With a zav on one pan and a surface made for lying or riding on the other, which side goes down decides which grade of impurity that surface takes, while other keilim, foods, liquids or a person on the opposite pan are a primary derivative of impurity whichever way the beam tipped. (8:6)
- Shaky things transmit and solid things do not. A pure man sharing a seesawing plank, a thin tree, an unnailed Egyptian ladder or an unmortared beam with a zav is impure because the thing shakes and the shaking is the zav moving him, while a large boat, a steady bench, a nailed ladder or a mortared beam leave him pure even on the same side; two men closing a door together are pure and one closing while the other opens is not; a zav who administers lashes makes the man he strikes impure, since he is leaning on him. (8:7, 8:8, 8:10)
- A finger above a body, and the Rambam's own note. A limb of a zav resting above a pure man, or a pure man's limb resting above a zav, defiles even with a stone or a beam between them, and teeth, nails and hair count as joined to the body for this, and the Rambam closes by writing that it appears to him that this impurity is of Rabbinic origin. (8:11)
RememberA person is present wherever his force arrives. That territory is much larger than the one he is standing in.
Ch 9His power, the room's trembling, and what does not pass down
- Whatever falls from his power is impure. When a zav bangs on a support that is joined to the ground and sound, keilim, food and liquids that fall from it are pure, and when the support is shaky they are impure even if they only shook without falling, since whatever falls as a direct result of the power of his movement is impure and whatever falls from the trembling of the support is pure. (9:1)
- The loaf and the shard. A loaf clinging to the wall of an oven that a zav knocks on is pure when it falls, even if it is terumah, and it is impure if a shard of the oven comes away clinging to it, even if it is ordinary food. (9:2)
- The midras keeps the rank and loses the reach. A surface that has contracted midras impurity conveys to keilim, food and liquids only by touching them, so anything above it or below it that is not in contact, even with a single sheet of paper between, is pure, and anything the impure surface itself causes to move is pure. (9:3)
- Clothing made impure by a doubt. A pure man sharing a small boat, a dinghy or one animal with a zav has clothes treated as midras, since perhaps the zav stepped on them, and so does a pure woman sitting on a bed with a woman in the niddah state, and the same decree covers a man pressing into a mill that shakes the floor hard enough to lift him off his place; the Rambam says plainly that these are decrees of doubt. (9:4, 9:5)
RememberHis force went through stone and through a thousand layers, and the mattress he sat on cannot move a cup.