according to the opinion of Rabbi Eliezer, that if they examined themselves on the first and seventh days they are considered to be pure during the intermediate days as well, what is the halakha? Do we require the first and last days of the seven, and if so, here there is an examination on the first day, and yet there is no examination on the last day, but only on the eighth day? Or perhaps Rabbi Eliezer requires an examination only on the first of the days, and this is sufficient even though there is no examination on the last of the seven days.

Rav said: This case of examining on the first and eighth days is the same as that of examining on the first and seventh days, i.e., Rabbi Eliezer requires an examination only on the first of the days, and this examination is sufficient even though there is no examination on the last of the days. And Rabbi Ḥanina said: We require an examination on the first and last days of the seven, and here there is an examination on the first day but there is no examination on the last day. Consequently, Rabbi Eliezer would not permit a zav or a zava to count any of the days in this case.

The Gemara raises an objection to the opinion of Rav from a baraita: And the Sages agree with regard to a zav and a zava who examined themselves on the first day and on the eighth day and found themselves to be ritually pure, that they have only the eighth day as part of their count. The Gemara asks: Who are the Sages who agree to this? Are they not Rabbi Eliezer and Rabbi Yehoshua? These two Sages, who disagree in a case where the zav and zava examined themselves on the first and seventh days, are evidently the ones who agree in the case of a woman who performed an examination on the first and the eighth days. This seems to contradict Rav’s opinion.

The Gemara rejects this suggestion: No, the Sages referred to here are Rabbi Yehoshua and Rabbi Akiva. Both of them agree that in this case the first day is not included in the count. Conversely, Rabbi Eliezer would say that the first seven days are included in the count and the eighth day is unnecessary, as there is a presumptive status of ritual purity from her examination on the first day.

§ The Gemara cites another discussion with regard to which days are included in the count of seven clean days. Rav Sheshet says that Rav Yirmeya bar Abba says that Rav says: A menstruating woman who performed the examination marking the first step in her transition from ritual impurity to ritual purity on her third day counts that day as part of the number of seven clean days.

The Gemara asks: Why does a menstruating woman require any kind of counting? If this is during her days when she is expected to menstruate she may immerse after the conclusion of seven days, whether or not those days were clean. Rather, say that Rav meant as follows: A zava who performed the examination marking the first step in her transition from ritual impurity to ritual purity on her third day counts that day as part of the number of seven clean days.

Rav Sheshet said to Rav Yirmeya bar Abba: Did Rav say his halakha in accordance with the opinion of the Samaritans, who say that the day on which a zava ceases to experience the emission of ziva counts toward the number of seven clean days, and she does not need to count seven complete days?

Rav Yirmeya bar Abba replied: When Rav says his halakha, he meant apart from the third day. Rav Sheshet challenged: If Rav meant apart from the third day, that is obvious; there is no need for him to issue such a statement at all. Rav Yirmeya bar Abba replied: No, the statement that she begins counting immediately after the third day is necessary for a case where once she saw that she was clean after the third day of her ziva emissions she did not examine herself again until the seventh day.

And Rav is teaching us two halakhot. There, in the previous discussion with regard to the opinion of Rabbi Eliezer, Rav stated that an examination at the beginning is sufficient, even though there is no examination at the end of the seven days. And here he teaches us that an examination at the end of the seven days is sufficient, even though there is no examination at the beginning of the seven days, but only on the day when she ceased experiencing bleeding.

Rav Yirmeya adds that it is necessary to teach both halakhot, lest you say that we say that an examination at the beginning is sufficient even though there is no examination at the end of the seven days, as we establish the clean days in accordance with their presumptive status. But one might have thought that Rav would not permit her to consider all the days to have been clean in a case of an examination at the end of the seven days even though there is no examination at the beginning of the seven days, where no presumptive status was established. Therefore, this second statement of Rav teaches us that even if she only examined herself at the end of the seven clean days it is sufficient.

The Gemara raises a difficulty with regard to Rav Yirmeya’s explanation. Is that so? But when Ravin came from Eretz Yisrael he said: Rabbi Yosei, son of Rabbi Ḥanina, raised an objection to the opinion of Rabbi Yehoshua ben Levi, that a woman who is uncertain whether or not she miscarried an actual fetus must bring an offering (see 29a). The reason is that the majority of pregnant women carry actual fetuses. Rabbi Yosef objected to this from the case of a woman who was forgetful, i.e., a woman who left town when she was pregnant, and later returned no longer pregnant. It is unknown whether she miscarried an actual fetus, and if it was a fetus, whether it was male or female. The conclusion there was that she does not have any days when blood she discharges is considered ritually pure, which is the halakha following a birth, as her miscarriage might not have been a fetus at all. Apparently, here one does not follow the principle that the majority of pregnant women carry actual fetuses.

Ravin continues: And I do not know what his objection is, as the reason that she does not have any days when blood she discharges is considered ritually pure is not only due to the uncertainty as to whether or not she miscarried a fetus, but because it is also unknown when that miscarriage occurred, i.e., even if she miscarried a fetus, perhaps the days when blood she discharges is considered ritually pure had already been completed. As we maintain that the first week that she comes before us, when the court is uncertain with regard to her impurity, we tell her to immerse every night of that week, in the manner of a woman purifying herself after menstruation or childbirth, but we do not tell her to immerse during the daytime, as she has not counted seven clean days (see 29b).

The Gemara explains how this discussion apparently contradicts Rav Yirmeya’s explanation. And if it enters your mind that we do not require all seven clean days to be counted before us, i.e., if an examination on the seventh day is sufficient, let us tell her to immerse also during the daytime, as perhaps she gave birth to a male baby during her days of ziva, and already performed her seven days of counting before she came before the court. The Gemara concludes: Rather, must one not conclude from this statement of Ravin that we require that her seven clean days be counted before us, which is why the court does not instruct her to immerse during the daytime.

The Gemara rejects this contention. But didn’t we interpret that the baraita is in accordance with the opinion of Rabbi Akiva, who said that we require her seven clean days to be counted before us? By contrast, Rav’s statement was in accordance with the opinion of Rabbi Eliezer, who holds that the days do not need to be counted before us.

§ The Gemara stated earlier that according to the opinion of the Rabbis, the seven clean days do not need to be counted before us. The Gemara analyzes their opinion: And from where do you say that according to the opinion of the Rabbis we do not require that the seven days be counted before us? This is as we learned in a baraita: With regard to a woman who was forgetful and does not know whether she is now in her days of menstruation or days of ziva, who said: I saw blood on one day of impurity, the court instructs her to immerse nine immersions.

The baraita clarifies: Since there is no way of knowing whether she is a woman purifying herself after menstruation or after ziva, she must immerse seven immersions on the following seven nights, for purification from menstruation, as each of these days might be the last of the seven days of menstruation. And she must also immerse during two days as purification from ziva, i.e., on the day that she arrives, in case she experienced bleeding the day before, and on the following day, as perhaps she experienced bleeding on the day of her arrival. But if this woman says: I saw blood at twilight that renders me impure, the court instructs her to immerse eleven immersions.

The Gemara asks: These eleven days, what is their purpose? If she would normally require nine immersions, why does she require an extra two immersions if she experienced bleeding at twilight? Rav Yirmeya of Difti said: The baraita is referring specifically to a case where she came before us at twilight and says that she also experienced bleeding at twilight, but it is not clear whether she experienced bleeding on a previous day at twilight, or today at twilight.

Rav Yirmeya explains: Therefore, she requires eight immersions to purify herself from menstruation, seven in case each of the following nights is the night after the seventh day of menstruation, and the eighth in case she experienced bleeding during twilight of the day she arrived, and this occurred in a time which was actually part of the next day, such that she needs to immerse also on the eighth night from her arrival, and three additional immersions during the day to purify herself from ziva. She must immerse during the day three times: She must immerse immediately, because if she experienced bleeding on the previous day during twilight it may have still been day, and right now, at twilight, it might still be day; she must immerse on the next day, because if she experienced bleeding on the previous day during twilight it may have already been night; and she must immerse during the day following the next day, because perhaps she experienced bleeding this twilight after it was night.

If this woman who is forgetful with regard to her cycle of menstruation and ziva says: I have not seen any blood at all, the court instructs her to immerse fifteen immersions. Rava said, in reference to this final halakha in the baraita: This halakha is not a logical halakha. Rather, it is like the halakha that they judge in a place named Galaḥi. In that place they follow the behavior of Sodom, and say that with regard to one who has one ox, he must shepherd the local flocks one day, and one who does not have an ox must shepherd the local flocks for two days. It is not logical that a woman who has not experienced a flow of blood must immerse more times than one who has experienced a flow of blood.

Apropos the mention of Galaḥi, the Gemara relates an incident that occurred in that place. There was an orphan in that town, the son of a widow [armelata], who had no oxen of his own. The people of that town gave him their oxen to shepherd. This orphan went and slaughtered all of the oxen. He said to the townspeople: Whoever has an ox should take one skin, while one who does not have an ox should take two skins. The people of Galaḥi said to the orphan: What is this that you are saying, i.e., what is the reason? He said to them: The end of the law is like the beginning of the law: Isn’t the beginning of the law that one who has no ox is preferred, and must shepherd the oxen for two days? So too, with regard to the end of the law, one who has no ox is preferred and should receive two hides.

The Gemara returns to discuss Rava’s comment with regard to the ruling of the baraita: Here too one can claim: And if in a case where she says: I saw blood, it is sufficient for her to immerse either nine immersions or eleven immersions, so too, in a case where she says: I did not see any flow of blood at all, is it logical that she requires fifteen immersions?

Rather, say that this is what the baraita means: If a woman says: I saw a flow of blood but I do not know how many days I saw blood, and likewise I do not know whether I saw the flow during the days of menstruation or if I saw the flow during the days of ziva, in such a case, the court instructs her to immerse fifteen immersions. The reason for these immersions is as follows: If she comes before us during the daytime, we give her seven immersions, beginning from that night, to remove the impurity of menstruation. Any of those seven nights might be the night after the last of her days of menstruation.