on her second day, after she immersed in a ritual bath. At that point, it is unclear whether she will remain clean of discharges for the remainder of the day, in which case she was pure from the time she immersed and may eat the Paschal lamb at night, or whether she will experience a discharge of blood during the day, in which case her immersion is retroactively invalid and she was impure the entire time. And after that, she saw blood, thus retroactively clarifying that at the time the Paschal lamb was slaughtered she was unfit to participate in it. The halakha is that she may not eat from the Paschal lamb due to her ritual impurity, but she is exempt from performing the ritual of the second Pesaḥ.

The Gemara explains: What is the reason that she is exempt from the second Pesaḥ? Is it not because the frontplate appeases God, and therefore her first Paschal lamb was valid? Consequently, it is clear that the frontplate does appease God for uncertain ritual impurity related to the discharge of a zava. Say in refutation of this proof: No, this is not the reason. Rather, it is because Rabbi Yosei holds that she renders objects impure from now and onward. When a woman who keeps watch a day for a day experiences another discharge on the second day after she immersed in a ritual bath, she is not retroactively considered to have been impure the entire time; rather, she begins a new period of impurity from the time of her second discharge. Therefore, when the Paschal lamb was slaughtered on her behalf, she was ritually pure.

The Gemara questions this refutation: Wasn’t the following taught in a baraita? Rabbi Yosei says: With regard to a zav who has had two sightings of discharge for whom they slaughtered a Paschal lamb and sprinkled its blood on his seventh day, after he immersed in a ritual bath, and subsequently on that same day he saw an additional discharge, which makes him ritually impure for another seven days; and similarly, with regard to a woman who keeps watch a day for a day for whom they slaughtered a Paschal lamb and sprinkled its blood on her second day after she immersed in a ritual bath, and subsequently she saw an additional discharge on that same day; these zavim render objects designed for lying and sitting impure retroactively. Once they experience an additional discharge, any object designed for lying or sitting upon which the zav or zava leaned between his or her immersion and the new discharge is considered to be retroactively impure from the time he or she leaned on it.

However, they are exempt from performing the ritual of the second Pesaḥ. This is proof that Rabbi Yosei holds that their ritual impurity is retroactive. Therefore, at the time the Paschal lamb is slaughtered, it is uncertain whether they are ritually pure or impure, because if they have another discharge before the end of the day, they are retroactively considered to have been impure the entire time. From the fact that they are exempt from the second Pesaḥ even if it turns out that they were ritually impure, it appears that the frontplate does appease God for uncertain ritual impurity due to the discharge of a zava.

The Gemara responds to this attempted proof. Say: What is the meaning of Rabbi Yosei’s statement that the ritual impurity applies retroactively? It means that the ritual impurity applies by rabbinic decree. However, according to Torah law, the zav or zava is impure only from the time of the new sighting and onward.

The Gemara points out that even Rabbi Oshaya holds that, according to Rabbi Yosei, a zav or zava renders objects designed for sitting or lying impure retroactively only by rabbinic decree in these circumstances. As it was taught in a baraita that Rabbi Oshaya says: But with regard to a zav who saw a discharge on his seventh day, it cancels the clean days that preceded it. And Rabbi Yoḥanan said to him: It should cancel only its day, i.e., the day on which he experienced the discharge, and he should require only one additional clean day.

The Gemara expresses surprise: Whichever way you look at Rabbi Yoḥanan’s statement, it is difficult: If he holds that that the zav renders objects impure retroactively, the new discharge should cancel all the days. Conversely, if he holds that the zav renders objects impure from now and onward, it should not cancel even its own day. Since part of the seventh day was clean, the zav is considered to have successfully completed his seven clean days, and the new discharge renders him impure for only one day. Rather, say instead that Rabbi Yoḥanan said as follows: It should not cancel even its own day.

And Rabbi Oshaya said to him: I do not agree with you, but know that Rabbi Yosei, who exempts one in this circumstance from the second Pesaḥ, holds in accordance with your opinion. The Gemara analyses Rabbi Oshaya’s statement: But didn’t Rabbi Yosei say that they render objects designed for lying and sitting impure retroactively, whereas Rabbi Yoḥanan holds that they render these items impure only from the time of the new discharge and onward? Rather, must one not conclude from this that when Rabbi Yosei said he renders these items impure retroactively, he meant that this ruling is due to rabbinic decree and is not Torah law? The Gemara concludes: Indeed, conclude from this.

The Gemara returns to its discussion of whether the leniency of impurity of the deep applies to priests and Rava’s attempt to prove that it does, based upon Rabbi Ḥiyya’s statement that impurity of the deep is permitted only with regard to ritual impurity imparted by a corpse. The Gemara asks: According to Rabbi Yosei, now that he said that a zav who immersed and then saw an additional discharge renders items impure only from now and onward according to Torah law, and not retroactively, Rabbi Ḥiyya’s statement that the leniency of impurity of the deep applies only to ritual impurity imparted by a corpse was stated to exclude what other case? Rabbi Ḥiyya could not have been excluding impurity due to the discharge of a zav or zava, as suggested above, because their offerings are valid even without the frontplate placating God.

Let us resolve the dilemma from this statement of Rabbi Ḥiyya, as it must come to exclude impurity from a creeping animal. If so, it must be referring to a priest, and impurity of the deep is permitted for him.

Say in response to this attempted proof: Actually, you can explain that it refers to the impurity of the owners and to a case where they are offering the Paschal lamb, and Rabbi Ḥiyya holds that one may not slaughter an offering and sprinkle its blood for those who are impure from a creeping animal. Therefore, it is necessary to clarify whether this halakha applies to those unknowingly rendered impure by a creeping animal, and it was necessary to exclude this case and teach that the leniency of impurity of the deep applies only to ritual impurity imparted by a corpse and not to impurity from a creeping animal.

The Gemara asks another question: But, according to the opinion of Rabbi Yosei, in the case of a woman who keeps watch a day for a day, under what circumstances can a full-fledged zava be found? If a new sighting does not retroactively render her impure, and it is considered as though it were the first sighting in a new series of discharges, how is it possible to link three sightings together to produce a full-fledged zava? The three sightings will always be considered separate.

The Gemara answers: A case of a full-fledged zava is found in a woman who continuously flows, i.e., she experiences a continuous discharge of blood that spans three days. If you wish, say instead that the case is where she saw a discharge for two entire twilights, meaning that she experienced a discharge for the entire twilight period on two consecutive days. In this case, there is no clean period separating the discharges at the beginning of a calendar day, and all of them are linked.

Rav Yosef raised a dilemma: With regard to the priest who facilitates acceptance of the daily offering, is ritual impurity of the deep permitted for him or not? The two sides of the dilemma are as follows: If you say that the priest who facilitates acceptance of the offerings of the nazirite and of one who performs the ritual of the Paschal lamb, ritual impurity of the deep is permitted for him, then in the case of the priest who facilitates acceptance of the daily offering, what is the halakha? Do we say that when we learned the halakha of impurity of the deep through oral tradition, it was with regard to the Paschal lamb, but with regard to the daily offering we did not learn it? Or perhaps we can derive that the halakha applies to the daily offering from the fact that it applies to the Paschal lamb?

Rabba said: This dilemma can be resolved through an a fortiori inference: Just as in a place where known ritual impurity is not permitted for him, e.g., with regard to the Paschal lamb, for which known impurity disqualifies the offering and one would have to observe the second Pesaḥ, nonetheless impurity of the deep is permitted for him, all the more so in a place where known ritual impurity is permitted for him, with regard to communal offerings, as such offerings may be sacrificed even in a known state of impurity if there is no way to sacrifice the offering in a state of purity,