(iii) Inanimate objects and corpse impurity. According to biblical law, every object or person that touches a corpse or shares a space with one becomes impure for seven days and can convey impurity further to whatever touches this object or person, which will in turn be impure for one day. For example, if a corpse is placed on a bed, the bed on which it lies will be impure for seven days, and if Jill then touches this bed, Jill will be impure for one day. The rabbis, however, rule that inanimate objects that touch a corpse become like the corpse itself, and whatever touches them will become impure for seven days and make whatever touches this object or person impure for one day.68 In the rabbinic scheme, then, the bed on which the corpse lies becomes like the corpse itself: if Jill touches the bed, she will become impure for seven days, and if Jill touches jack, he will become impure for one day (whereas in the biblical scheme Jack would not be affected at all). Furthermore, the rabbis rule that if an inanimate object touches something that has had contact with a corpse—that is, something which is impure for seven days—the inanimate object itself becomes impure for seven days, making whatever touches it impure for one day. To return to our example, if Jill touched the bed on which a corpse was placed, Jill becomes impure for seven days; if Jill then touches a cup, the cup becomes impure for seven days, like Jill; and if Jack then touches the cup, he becomes impure for one day. This means that even something or someone three times removed from a corpse can contract the same degree of impurity as something or someone that touched it directly.69
These three principles of duplication of impurity, whether they originated in the rabbinic system or were inherited from earlier interpretive traditions, amount to a significant expansion of the realm and repercussions of impurity. If impurity can be contracted not only directly from the source but also, in certain settings, from something that had contact with the source, then the presence of impurity in the world becomes much more pervasive and, at the same time, can much more easily escape one’s consciousness: while one is likely to know if one touched an impure person, one is much less likely to know if one touched something that was touched by an impure person. This pervasiveness of impurity and its enhanced transferability in the mishnaic impurity system thus lead to a new perspective on impurity, at the center of which stand not the primary sources of impurity, but those who are likely to contract it.
The enhanced transferability of impurity in the Mishnah is manifested not only through the mechanisms of the duplication of impurity, some of which may date back to earlier traditions, but also in the construction of new modes of contraction of impurity that notably expand the Priestly paradigms of impurity transmission. These new modes of transmission, which to the best of my knowledge have no precedent in biblical or postbiblical literature, substantially increase the possibility of an inadvertent and unaware contraction of impurity, thus further increasing the pervasiveness of impurity in everyday encounters and experiences.
The Expansion of Biblical Modes of Impurity Transmission.(i) Expansion of the biblical “tent.” According to the Priestly Code, the human corpse is the only source of impurity that conveys impurity not only to whomever touches or carries it, but also to everyone and everything that shares the same “tent” with it.70 While the biblical verse seems to indicate that corpse impurity is conveyed only when one shares a specific confined space with the dead, the rabbis develop and expand the category of “tent” to include every kind of shared overhang (ahel, from the noun ohel, “tent”) with the dead. According to the Mishnah, everything and everyone that is (1) situated under the same roof as a corpse, (2) situated under a corpse so that the corpse overshadows it, or (3) situated above a corpse so that it overshadows the corpse is deemed impure.71 In this way, the rabbinic perception of overhang, which turns the biblical tent into a wholly abstract category, actually turns almost every kind of copresence with the dead into a form of physical contact. For instance, a person who stands under the shadow of a tree that also shadows a graveyard is rendered impure, even though she herself is completely outside the graveyard. The result of this rabbinic innovation is that corpse impurity becomes wildly more present in the world of the everyday: corpse impurity is no longer only the concern of the immediate relatives of the dead or those who share the same habitation with it, but is also the concern of the passersby who happen to stumble upon a dead body on the side of the road (which was not uncommon in the ancient world) or to pass next to a grave, even without touching it.72
(ii)“Shift” impurity. Apart from the case of corpse impurity, in which impurity is also conveyed through shared space, there is only one way in which impurity can be conveyed in the biblical scheme, namely, through direct physical contact.73 The rabbis, however, introduce a new mode of impurity contraction that does not involve direct contact, which they call “shift” (heset). The category of shift pertains to any setting in which the source of impurity causes something else to move from its place, even without direct contact.74 The quintessential example of this is a case in which a man with genital discharge is placed on one side of a scale and foods and liquids are placed on the other side of the scale: if the man’s weight tips the scale and causes the foods and liquids to move, they are rendered impure.75 As several passages in tractate Zavim powerfully portray, the meaning of this form of contraction is that almost every daily activity in which a pure person and an impure person both partake, even without touching each other, can cause the pure person to contract impurity. To take just two examples:
If a man with genital discharge and a pure man sat together in a boat or a raft, or rode an animal together, even though their clothes do not touch—[the clothes of the pure person] are impure on account of treading (teme’in midras, that is, impure as if the impure person physically trod on them).
If they both sat on a beam, on a bench, on a railing of a bed, or on a pole while those are wobbly, if they climbed a tree that is unsteady . . . [the pure one’s clothes] are impure. (M. Zavim 3.1)
R. Yehoshua says: If a menstruating woman sat with a pure woman in the same bed—the cap at the top of [the pure woman’s] head is impure on account of treading.
If she sat in a boat, the items at the top of the mast are impure on account of treading. (M. Zavim 4.1)
As these passages make clear, the notion of impurity contraction through shift makes the very physical presence of impure persons so powerful that the repercussions of indirect contact with them are identical to the repercussions of direct contact. In other words, the concept of shift-impurity inscribes everyday activities and interactions with a heightened potential of impurity: one need not only be careful whom one touches, but even with whom one sits, works, plays, rides, and so forth.
(iii) Bodily fluids. While the biblical text makes it clear that persons with genital discharges are impure as such, and that mere contact with the external surface of their bodies suffices to convey impurity, it also implies that the most immediate source of impurity in these cases is the genital discharge itself. The rule that whatever the person with genital discharge sits, lies, or rides on is as impure as the person herself strongly suggests that the genital emissions were seen as the actual cause of impurity.76 The rabbis make this point explicit, determining that menstrual blood and abnormal genital emissions convey the same kind of impurity as the persons who emitted them, but they also maintain that the innocuous bodily fluids of impure persons, namely, their urine and saliva, convey the exact kind of impurity as the impure persons themselves.77 This idea is not entirely without biblical precedent, since the Priestly Code does mention that if a person with genital discharge spits on another person, the other person becomes impure.78 But whereas the Priestly text seems to envision spitting as a form of direct contact with the impure person, the Mishnah maintains that even if one encounters the bodily fluids of an impure person in