Taharos, Chapter 1, Mishnah 1. Our masechta shares its name with the seder in which it stands, and that name has a touch of irony to it: the overwhelming majority of what we will study concerns items that are tamei. The title is really a polite substitute, a softer way of naming a harsh subject. Across the ten perakim before us we will take up neveilah, the tumah that liquids carry, the halachos that govern one who is not careful about taharah, and, before we finish, we will have acquired a working knowledge of how olive oil is pressed, more than most of us ever imagined we would need. Wherever possible, the explanation offered here tracks the approach of the Bartenura.
The opening mishnah of the masechta deals with nivlas ha'of hatahor: the carcass of a bird that died on its own rather than being slaughtered, and which belongs to a tahor species. Here the word tahor needs care. Just as in ordinary Jewish speech "treif" is used loosely and not in the Torah's precise sense, so too here: calling the bird tahor does not mean that it is ritually pure, and it certainly does not mean that it is fit to eat. It means only that it comes from a species included among the birds a Jew may eat, a chicken rather than a vulture.
Where does the Torah discuss such a bird? Turn to Vayikra, perek 17, pasuk 15:
"V'chol nefesh asher tochal neveilah u'tereifah, ba'ezrach uvager, v'chibes begadav v'rachatz bamayim, v'tamei ad ha'erev v'taher."
The pasuk teaches that a person who consumes a neveilah or a tereifah, native-born or convert alike, launders his clothing, immerses in water, and remains tamei until the evening, after which he is pure. Chazal read this verse as addressing a bird, and not just any bird but one of a species the Torah permits. Much is learned from the exact language the pasuk chose: eating is what triggers the tumah. Contrast this with the carcass of a behemah, which transmits tumah to whoever touches it or carries it. A bird carcass works differently. It becomes a source of tumah only through consumption, and the moment it reaches the eater's gullet he begins conveying impurity to the clothes he is wearing and to any keilim in his hands. This will also explain why the shiur required for nivlas ha'of is what it is: since eating rather than contact is the mechanism, the measures follow suit.
The mishnah opens: "Shloshah asar davar b'nivlas ha'of hatahor," there are thirteen matters that distinguish the neveilah of a kosher-species bird. Nine of them appear in this mishnah, and the remaining four in the mishnah that follows.
- "Tzerichah machshavah." It requires intent. Throughout the halachos of tumah and taharah, a substance must have been designated as food in order to receive food-tumah. Since a bird that died on its own is not kosher, we would not automatically assume it is food at all. Therefore one must actively think about it "l'achilas adam," that it be eaten by a person, for example by a non-Jewish neighbor. The Bartenura notes from Masechta Uktzin that this requirement is not universal: in large towns, where neveilah is regularly sold, no such thought is needed, and the rule of the mishnah applies to small towns.
- "Einah tzerichah hechsher." It does not require hechsher, that is, it need not first be wetted in order to be susceptible to tumah. It is inherently tamei, carrying the status of a rishon.
- "U'metam'ah tum'as ochlin b'kabeitzah." It conveys food-tumah in the measure of a kabeitzah. In the words of the Bartenura, a kabeitzah of it that touches tahor foods renders them tamei. This measure will recur constantly in the masechta: wherever we are dealing with a food conveying tumah, the shiur is a kabeitzah.
- "Uk'zayis b'veis habeli'ah." A kezayis, the smaller measure of an olive's bulk, suffices when the food is in the throat. One who is in the middle of eating the neveilah bird conveys impurity with only a kezayis.
- "U'te'unah he'erev shemesh." One who became tamei from it requires nightfall. Immersion in a mikveh alone does not finish the job; there is also a built-in delay until the sun sets.
- "V'chayavin aleha al bi'as hamikdash." As with other forms of tumah, one who enters the Mikdash while tamei from it is liable.
- "V'sorfin aleha es haterumah." If it touched terumah, that terumah must be burned. This is a theme we will encounter repeatedly through the masechta.
- "V'ha'ochel eiver min hachai mimenah sofeg es ha'arba'im." One who eats a limb taken from it while it was still alive receives the forty lashes, even for less than the standard measure. The Bartenura points out that this clause runs against the shitah of Rebbi Meir, who holds that the prohibition of eiver min hachai applies only to behemos. That will matter in a moment: Rebbi Meir is not the author of the whole mishnah, only of the final clause.
- "Shechitasah u'melikasah metaheres es terefasah." If one performed shechitah on the bird, or melikah, pinching the neck, and it was subsequently found to have been a tereifah, that act purifies it from the tumah of neveilah. Shechitah is the procedure used outside the Mikdash; melikah is the procedure used inside the Mikdash for birds. This is the position of Rebbi Meir, who reasons by a kal vachomer: if shechitah and melikah are effective to purify behemos, which convey tumah through carrying and touching, then all the more so they should be effective for birds, whose tumah operates only through eating.
The mishnah closes with the dispute over that last point. "Rebbi Yehudah omer: einan metaharos." Rebbi Yehudah rejects the comparison and refuses to derive the law of birds from behemah; neither shechitah nor melikah purifies. "Rebbi Yosi omer: shechitasah metaheres, aval lo melikasah." Rebbi Yosi draws a line between the two acts: shechitah accomplishes the purification, melikah does not.
Nine of the thirteen distinctions have now been counted. The remaining four are taught in the next mishnah.