Zavim, Chapter 3, Mishnah 2. This chapter deals with a zav and a tahor person who find themselves together in one place or engaged in one shared activity, in circumstances where it is quite possible that the zav shifted or leaned against the other man without either of them noticing. Where that possibility is real, the tahor man contracts what is called tumas heseis. Our mishnah applies that principle to a whole series of ordinary tasks that two people do together.
Opening and Closing a Door
The mishnah begins with a zav and a tahor person who were "megifin o poschin", closing a door or opening it. According to the first opinion, whichever of the two operations they were engaged in, whether shutting the door or pulling it open, the tahor man becomes tamei through heseis.
The Chachamim disagree and restrict the case. They require that the two men be working at cross purposes: "ad sheyehei", until it is the situation that "zeh megif", this one is pushing the door shut, "vezeh posei'ach", while that one is drawing it open. Only then does the zav transmit tumah to his companion. What makes this case different is that each man is exerting force from the opposite side, so that neither has his mind on the other, and the chance that one bumped or pressed against the other without noticing is a genuine one. That is exactly what heseis means: no one can testify that any touch occurred, yet the setting makes it thoroughly believable that it did.
Pulling Each Other Out of a Pit
The next case is "ma'alin zeh es zeh", they raise each other up, "min habor", out of a cistern. In such a case the tahor man becomes tamei. The Rambam differentiates between the two directions this can take. Should the zav have been the one hoisting his companion up, the man who was raised has only heseis. Should it have gone the other way, with the tahor man doing the lifting while the zav is the one raised, his tumah is of a heavier sort: he has physically borne a zav, and he is therefore tamei by masa, with everything that carrying a zav entails.
Rabbi Yehuda maintains that the tumah applies in one direction alone: "ad sheyehei hatahor", until it is the tahor man who is "ma'aleh es hatamei", hoisting up the tamei one. In that arrangement the zav, while being raised, is liable to have rested his weight upon the man beneath him. Where the roles are reversed and the lifting is being done by the zav, Rabbi Yehuda finds nothing to worry about. We do not rule in accordance with Rabbi Yehuda.
Twisting Ropes
Twisting Ropes
"Mafshilin bachavalim": should the zav and his tahor companion have been twisting ropes side by side, the tahor man becomes tamei. Once again the Chachamim confine the ruling to a specific arrangement: "ad sheyehei", until it is the case that "zeh mosheich eilach", this one hauls the rope toward himself, "vezeh mosheich eilach", and that one hauls it toward his own side. It is the tug from opposing sides that makes it genuinely plausible that the zav pressed against the man beside him.
Weaving and Grinding
"Orgim": if the two of them were weaving together, the mishnah rules that the tahor man becomes tamei, "bein omdim bein yoshvin", whether the weaving was done standing or sitting. The same applies to "tochanin", when they were grinding together.
"Rabbi Shimon metaher bekulan": in Rabbi Shimon's view the tahor man stays tahor throughout this entire list, "chutz min hatochanin", apart from those grinding, "bereichayim shel yad", at a mill turned by hand. In that instance the pair are crowded so closely over their work that any thought of the tumah standing between them slips away, and the odds are high that the zav pressed against his companion. So that alone is the exception Rabbi Shimon grants. Here too the halachah rejects Rabbi Shimon's position, and our practice is the stricter one.
Loading and Unloading
"Porkin min hachamor, o to'anin": if the two of them were unloading a donkey together, or loading it, they are tamei. Why? Because when two men handle a burden together it is quite possible that the zav rested some of his weight on his fellow, and that leaning conveys tumah.
But that assumption holds only where the load was substantial. "Bizman shemasa'an kal, tahor": if the burden was a light one, the man remains tahor. With a light load the two of them can carry it while standing well apart from one another, and there is no reason to suppose that they came into contact or that the zav leaned on the tahor man at all. Where the concern evaporates, so does the tumah.
The Standing of One Who Is Tamei Through Heseis
The mishnah closes with a general ruling that applies to every case it has listed: "vechulan tehorin leveis haknesses utmei'in literumah". All of these people, who contracted tumah only through the heseis of a zav, are still considered tahor for beis haknesses, and they may continue to eat chullin in a state of purity. The reason is that heseis of this kind never amounts to more than a safeik, a doubt as to whether contact actually occurred; it is not a case in which we know that tumah was transmitted. Such a person is likewise not relegated to the section reserved for those who are genuinely a zav; his status is a lighter one.
The Rabbanan, however, decreed that he may not eat terumah, since terumah is guarded at a far higher standard of purity than ordinary, mundane food.