Chullin, Chapter 6, Mishnah 4. This chapter is devoted to the mitzvah of kisuy hadam, covering the blood of a slaughtered chayah or bird. Our mishnah addresses a practical question that arises the moment more than one animal is involved: does every slaughtering generate its own separate act of covering, or is the mitzvah measured by the blood that lies before us?
Consider the scenario the mishnah presents. "Shachat me'ah chayot," one slaughtered a hundred wild animals, and he did so "bemakom echad," all of them in one and the same spot. The ruling is "kisuy echad lekulan": he covers a single time and has thereby covered for the entire hundred. Fowl are no different. Had he slaughtered "me'ah ofot," a hundred birds, gathered in one place, again one act of covering answers for all of them.
One might have assumed that each slaughtering carries its own private obligation, so that a hundred slaughterings would demand a hundred coverings. The mishnah teaches otherwise. The mitzvah is defined by the blood being covered, not by a count of animals. One complete act of covering that leaves the blood covered discharges the obligation entirely.
When an Animal and a Bird Are Slaughtered Side by Side
Next comes a mixed case: "chayah va'of," a wild animal together with a bird, slaughtered "bemakom echad," in the same location. Once again the halacha is that one covering serves them both. The mistaken notion being ruled out here is of a different sort. The Torah mentions a chayah and it mentions an of, and one might therefore have imagined two independent mitzvot, each demanding its own covering. Not so, says the mishnah. There is one mitzvah of kisuy hadam, and a single performance of it takes care of the animal's blood and the bird's blood together. One action, and the obligation is met.
Rebbi Yehuda's View
"Rebbi Yehuda omer," Rebbi Yehuda takes a different position. "Shachat chayah, yechasena": once the wild animal has been slaughtered, its blood is to be covered right away, and only then, "ve'achar kach yishchot et ha'of," does he go on to the shechitah of the bird, whose blood is then given a covering of its own.
Rebbi Yehuda's proof lies in how the pasuk phrases things. The Torah writes "chayah o of," placing an "or" between the animal and the bird, and to Rebbi Yehuda that separation is instructive: even when the two are slaughtered in one session, the blood of each calls for a covering by itself. For him the whole progression is a mitzvah in its own right in each instance: shechitah of the chayah, then kisuy of its blood; shechitah of the of, then kisuy of its blood.
When the Shochet Fails to Cover
"Shachat velo chisa vera'ahu acher, chayav lechasot." A person slaughtered a chayah or a bird and neglected the covering, transgressing the halacha in the process. Now a bystander comes along and finds the blood lying exposed. That bystander himself becomes obligated to cover it.
Scripture states, "veshafach et damo vechisahu be'afar," he shall spill out its blood and bury it in dust. The obligation, then, belongs to the one who spilled the blood, that is, the shochet himself. Yet if the shochet lets his duty go unfulfilled, the mitzvah does not simply lapse, for the very next pasuk declares, "va'omar livnei Yisrael," Hashem addresses the entire Jewish people. The mitzvah thereby falls on all of them: once the slaughterer has defaulted, anyone who comes upon blood still lying uncovered is charged with covering it.
Blood That Becomes Uncovered Again
"Chisahu venitgala, patur milechasot." If a person covered the blood properly and afterward it became uncovered, he is exempt from covering it a second time. The mitzvah of kisuy hadam is fulfilled with a single performance, and having performed it, he owes nothing further.
"Chisahu haru'ach, chayav lechasot." If the wind blew earth over the blood so that it became covered on its own, and then the blood was subsequently exposed again, he is obligated to cover it. The distinction is straightforward: in this case the covering was never really done by him at all, it happened by itself. Since he has not yet performed the mitzvah even once, the obligation still stands, and he must now go and cover the blood.