Rava said: With regard to one who examined, found a corpse, and removed it from its place, and again examined nearby, found another corpse, and removed it from its place as well, if he examined yet again and discovered a third corpse, he does not move this third one alongside these two he has already moved, as he now knows that this was a graveyard and the corpses were buried there intentionally. And he does not return these two alongside this one either, as he is not obligated to restore the corpses to their prior locations after they have been reburied.

There are those who say that Rava said: Since permission was granted to move the first and second corpses, one may therefore move them all, including the third one. The Gemara asks: And let us deem them part of a graveyard. Since three corpses were found buried together, there might be others in the vicinity. Reish Lakish said: They found a pretext and deemed Eretz Yisrael ritually pure. Since at that point there was just one corpse, the Sages were lenient and were not concerned about any further impurity. The Sages wished to avoid uncertain impurity because people were careful to observe the halakhot of ritual purity in Eretz Yisrael, and additional cases of uncertain impurity would be complicated to observe.

The Gemara asks another question: If one examined twenty cubits from the location of those corpses and did not find anything, what is the halakha? Rav Menashya bar Yirmeya says that Rav says: This is a graveyard. Those three corpses compose the graveyard and there is no concern for others. The Gemara asks: What is the reason for this ruling? Why is there no concern that there might be many more corpses in the surrounding area? Once again Reish Lakish said: They found a pretext and deemed Eretz Yisrael ritually pure. Eretz Yisrael is deemed pure in a case of uncertainty.

MISHNA: Any case of uncertainty with regard to leprous sores is initially deemed pure until it is established that it is a case of ritual impurity. Once it has been determined to be a case of impurity, uncertainty concerning it is deemed impure.

GEMARA: The Gemara asks: From where are these matters derived? Rav Yehuda said that Rav said: The verse states: ''This is the law of the plague of leprosy…to pronounce it pure or to pronounce it impure'' (Leviticus 13:59). Since the verse opened with purity first, this teaches that any case of uncertainty concerning leprous sores is deemed pure. The Gemara asks: If so, if the halakha is based on this verse, then even once it has been determined to be a case of impurity, uncertainty concerning it should be deemed pure as well, as this interpretation of the verse should apply to all cases of uncertainty with regard to leprosy.

Rather, when this statement, that Rav Yehuda said that Rav said, was stated, it was stated with regard to the following dispute in a mishna concerning an uncertain leprous sore (Nega’im 4:11): If the snow-white leprous sore [baheret], which is one sign of leprosy, preceded the white hair, which is another sign, he is impure. This halakha is stated in the Torah (see Leviticus 13:3). And if the white hair preceded the baheret he is pure, as this is not considered a sign of impurity. If there is uncertainty as to which came first, he is impure. And Rabbi Yehoshua said: Keiha.

The Gemara asks: What is the meaning of keiha? Rav Yehuda said: Rabbi Yehoshua pronounced the matter unsolvable and ruled it is pure. The Gemara further asks: And perhaps this means that he pronounced the matter unsolvable and ruled it is impure? Rav Yehuda said that Rav said: The verse states: ''To pronounce it pure or to pronounce it impure'' (Leviticus 13:59); since the verse opened with purity first, any case of uncertainty concerning leprous sores is deemed pure.

MISHNA: This mishna discusses another case that includes the statement: There is a basis to anticipate the matter. One examines a man who experienced a gonorrhea-like discharge [zav] in seven ways, as long as he has not been confirmed as having a gonorrhea-like discharge [ziva]. With regard to an individual’s second such discharge, before he has been established as a greater zav, one examines to see whether there may have been a particular trigger of his discharge. One examines him with regard to food and with regard to drink, in case the discharge might have been the result of overeating or excess drinking; with regard to a burden, as it might have been caused by the weight of a heavy burden; and with regard to jumping, in case he jumped and this led to the discharge; and with regard to sickness; and with regard to an arousing sight; and with regard to the thought of a woman.

Once he has been confirmed as having a ziva, after two definite discharges of ziva, one no longer examines him in this way, as any discharge is deemed impure. If one experiences three discharges of ziva, he is obligated to bring an offering following his purification. Accordingly, his discharge that was due to circumstances beyond his control, i.e., for one of the seven reasons listed above, and his discharge about which it is uncertain if it is ziva, and even his semen, which is not usually considered the discharge of a zav, are all impure. Why is this so? It is because there is a basis for anticipating the matter. Once he has the status of a zav, it can be assumed that subsequent discharges are of ziva as well.

The Sages similarly taught: With regard to one who strikes another with heavy blows, and doctors assessed that he would die as a result of the beating, but his health improved from what it was, so that they then determined that he would not die from his injuries, and afterward his condition worsened and he died, the one who struck him is liable to receive court-imposed capital punishment, as it is assumed that the victim’s death was caused by the assault. Rabbi Neḥemya says: He is exempt, because there is a basis for anticipating the matter. Since the victim began to recover during his illness, it is reasonable to assume that his death was caused by a factor other than the assault.

GEMARA: The Gemara asks: From where are these matters derived, that one examines a zav before he has been confirmed as having a ziva, but not after? Rabbi Natan says that the verse states: ''And the zav who has an issue [zav et zovo], whether it is a man or a woman'' (Leviticus 15:33). This teaches that after two discharges, corresponding to the words zav and zovo, with regard to the third sighting, when one is already a zav, the verse juxtaposes the halakha of a male to that of a female: Just as it makes no difference in the case of a female whether her discharge of menstrual blood was triggered by an external factor, as she is ritually impure regardless, once a male zav has the status of impurity, one no longer examines him to see if his discharge was triggered by an external factor.

The Gemara asks: But isn’t it taught in a mishna (Zavim 2:2) that Rabbi Eliezer says: For the third discharge one still examines him; for the fourth discharge one does not examine him. Where does the verse allude to the fourth discharge? The Gemara answers: Rather, they disagree with regard to instances of the word ''et,'' i.e., whether or not the word ''et'' teaches an additional halakha, or whether it is written purely for syntactical reasons. Rabbi Eliezer expounds instances of the word ''et,'' and therefore he counts the phrase ''zav et zovo'' as three words referring to three discharges. And the Rabbis do not expound instances of the word ''et,'' which means that in their opinion this verse alludes to only two discharges.

§ The mishna taught that his discharge that was due to circumstances beyond his control, and his discharge about which it is uncertain if it is ziva, are considered impure.