The sacrifices discussed in the first chapters of Tractate Zevachim involved the slaughter of large animals such as bulls and sheep. With Chapter Seven, the focus moves to bird offerings—the doves and pigeons that are prescribed for sacrifice in the Torah. Bird offerings, too, come in two varieties: sin offerings, whose meat is set aside for consumption by the priests, and burnt offerings, which are burned whole on the altar. Much of the Talmudic discussion revolves around problems that arise when one type of sacrifice is accidentally performed as the other type: Are the offerings still valid, and can they be eaten without communicating impurity?
Animal slaughter is always a messy process, but in the case of bird offerings things got especially up close and personal. In Leviticus, the Torah commands that the priest “pinch off” the head of the bird, and in Zevachim 64b, at the end of Chapter Six, the mishna explains just what this entails. The priest does not use a tool to perform this pinching, but actually uses his thumbnail to break the bird’s neck and sever its windpipe. In the Gemara, Rav illustrates how this was done: the priest holds the bird in the palm of his hand, with two fingers over the wings and two fingers over the legs, leaving the thumb free to pinch the nape of the bird’s neck. A baraita, however, offers a different explanation, holding that the priest held the bird on the back of his hand, using his thumb to bend the neck forward into his palm. Of course, neither Rav nor any of the other sages had actually seen a bird sacrifice being performed, so these could only be hypotheses. But the rabbis have no doubt that bird sacrifice required a good deal of manual strength and dexterity: “And this is the most difficult sacrificial rite in the Temple,” the Gemara observes.
In the case of a sin offering, the bird’s head remains attached to its body—one can picture it hanging limply to the side—and the priest sprinkles its blood on the altar directly from the bird’s open throat. After the sprinkling, the priest “squeezes” the corpse so that all the remaining blood comes out on the base of the altar. At that point, the bird is ready for the priests to cook and eat it. With a burnt offering, the procedure is slightly different. The priest would use his fingers to pinch off the bird’s head completely, then squeeze out the blood from the body and the head separately at different places on the altar. He would then use salt to absorb all the remaining blood from the head and toss the bloodless head onto the fire, where it would be consumed. The body required its own special preparation: again using his bare hands, the priest would extract the bird’s crop, tear the whole carcass in half lengthwise, and throw the body into the fire. The mishna explains that the two halves of the bird should not be completely separated when they are torn, though if they come apart accidentally, the offering is still valid.
In Chapter Seven, the mishna goes on to explain that the sacrificial process involves two parts, the pinching of the neck and the squeezing of the blood. With a sin offering, both parts must be performed with proper intention if the sacrifice is to be valid: That is, if the priest pinched the neck of a sin offering while thinking that he was performing a burnt offering, the sacrifice does not count. But things are different the other way around: If the priest performs a burnt offering in the belief that he is performing a sin offering, the sacrifice is still valid, although it does not discharge the obligation of the person who brought it.
Can a disqualified bird offering be eaten without fear of committing a sin? The answer, as the mishna explains in Zevachim 66b, is yes and no. In terms of kashrut, there is nothing to worry about, because an offering slaughtered by priests, even improperly, “does not render one who swallows its meat ritually impure when the meat is in the throat.” In other words, once the bird’s neck is pinched off by a priest, the animal is considered properly slaughtered, and it does not assume the legal status of a carcass—an animal that has died on its own or that was killed improperly. Such carcasses are strictly forbidden for Jewish consumption. But this doesn’t mean that an improperly sacrificed bird can be eaten freely, because the bird still remains the property of the priests. As a result, “one who derives benefit from them is liable for misusing consecrated property.”
What are some of the mistakes that can invalidate the slaughtering process? The mishna in Zevachim 68a explains that a bird sacrifice must be performed with the thumbnail of the priest’s right hand, during daylight hours, and in the Temple courtyard. Any deviation from these rules—for instance, if the priest killed the bird with his left hand—renders the sacrifice invalid, but again, it does not make the meat unkosher. However, more serious mistakes do render the bird’s meat unfit for consumption. These include the use of a knife to cut off the bird’s head, instead of the priest’s own hand, or the sacrifice of birds that have a physical deformity, such as blindness or a withered wing. It is a general rule that only perfect specimens can be offered for sacrifice; God’s honor demands nothing less.