If she said: I saw twelve impure days, i.e., I had a discharge of blood for twelve days, the alleviation of her state of uncertainty occurs after she experiences eight clean days, to account for the worst-case scenario that the first two days of discharge occurred on the last two of the eleven days of ziva and the other ten occurred on the seven days of her menstrual cycle and the three subsequent days. If so, she would have another eight days until the end of the full eighteen-day cycle, and when she next experiences a discharge it is the beginning of her new menstrual cycle.

If she said: I saw thirteen impure days, i.e., I had a discharge of blood for thirteen days, the alleviation of her state of uncertainty occurs after she experiences seven clean days, to account for the possibility that the first two days of discharge occurred on the last two of the eleven days of ziva and the others occurred on the seven days of her menstrual cycle and the four subsequent days. If so, she would be left with only seven more days until the end of the full eighteen-day cycle, and when she next experiences a discharge it is the beginning of her new menstrual cycle.

All this shows that there is no alleviation of a woman’s state of uncertainty if she had a discharge of blood and is unsure whether it was during her days of menstruation or during her days of ziva in fewer than seven clean days and in no more than seventeen clean days.

Rav Adda bar Ahava said to Rabba: Why do I need all of these clean days? Let her count a mere seven clean days and be permitted to her husband. Regardless of whether the bleeding occurred during her days of menstruation or during her days of ziva, a woman can immerse in a ritual bath and become ritually pure and permitted to her husband after a maximum of seven clean days.

Rabba said to him: We say that she must experience seventeen clean days only with regard to setting her right concerning her status as a menstruating woman and the alleviation of her state of uncertainty. It is true that a woman can always become permitted to her husband after seven clean days. The discussion in the mishna and baraita concerns the resolution of uncertainty about whether her next discharge of blood will render her a menstruating woman or a zava. This is significant because if she is menstruating she can become ritually pure and permitted to her husband after seven days even if none of them are clean days, whereas if the discharge occurred over one or two days during the eleven days of ziva, she becomes pure after one clean day; and if the bleeding lasts three days or more during that time, she must wait for seven clean days.

§ The Sages taught in a baraita: All women who experience a discharge of blood and are unsure whether it is during the days of menstruation or the days of ziva are considered zavot. Therefore, they must bring the offering of a zava, in case they have this status; but it is not eaten by the priests, due to the possibility they were not actually zavot. This is the case for all women, except for a woman who experiences a discharge for thirteen consecutive days, whose alleviation of her state of uncertainty occurs after seven clean days, and for a woman who experiences a discharge for twelve consecutive days, whose alleviation of her state of uncertainty occurs after eight clean days. In those two instances, the women bring the offering of a zava and it is eaten by the priests.

The Gemara asks: Is that to say that all women who experience a discharge of blood and are unsure whether it is during the days of menstruation or the days of ziva are considered zavot? It is in fact unknown whether they are menstruating or are zavot. And furthermore, is a woman who experienced a discharge for one day or for two days fit to bring an offering? Only a zava who experienced a discharge for three consecutive days is required to bring an offering.

The Gemara answers: Rather, the baraita means that all zavot, i.e., women who experienced a discharge for three consecutive days, who are unsure whether their discharge took place during the seven days of menstruation or the eleven days of ziva, can become ritually pure after seven clean days, at which point they bring an offering, but it is not eaten by the priests. This, the baraita continues, is the case for all women except for a woman who experiences a discharge for thirteen consecutive days, whose alleviation of her state of uncertainty occurs after seven clean days, and for a woman who experiences a discharge for twelve consecutive days, whose alleviation of her state of uncertainty occurs after eight clean days. These women bring the offering of a zava and it is eaten by the priests.

MISHNA: There are symptoms of leprosy that a priest will immediately confirm to be ritually pure or ritually impure, and there are others for which the priest quarantines the leper in order to determine his status. With regard to leprous marks, there is no quarantine that is less than one week and none greater than three weeks.

GEMARA: When the mishna states that there is no period of quarantine less than one week, it is referring to leprous marks that affect a person, as the priest issues a definitive decision about leprous symptoms on an inflammation or a burn after one week (see Leviticus 13:18–28). When the mishna states: And none greater than three weeks, it is referring to leprous marks that affect houses, as there are instances when a definitive decision is rendered only after the house has been quarantined for three weeks.

§ Rav Pappa says: In the phrase: “Your benevolence is like the mighty mountains” (Psalms 36:7), these acts of benevolence are referring to leprous marks that affect a person. When God punishes someone with benevolence, He afflicts the individual with leprous symptoms on his body that can be resolved in just one week. When the verse continues with the phrase, “Your judgments are like the great deep,” these judgments are referring to leprous marks that appear on houses, the status of which can take up to three weeks to be determined.

The Gemara asks: To what does the plain meaning of the aforementioned verse refer? Rav Yehuda said that the plain meaning of the verse is as follows: If not for the fact that Your benevolence is like the mighty mountains, who could withstand Your judgments, which are like the great deep? Rabba says the verse should be understood differently: Your benevolence is like the mighty mountains, because Your judgments are like the great deep.

The Gemara asks: With regard to what principle do Rav Yehuda and Rabba disagree? The Gemara answers that they disagree with regard to the dispute between Rabbi Elazar and Rabbi Yosei, son of Rabbi Ḥanina, about how God applies His attribute of “abundant in kindness” (Exodus 34:6) when He judges a person whose merits and sins are equal. As it was stated that Rabbi Elazar says: He hides away some sins and does not put them on the scale, thereby allowing the merits to outweigh the sins. Rabbi Yosei, son of Rabbi Ḥanina, says: He lifts the side of the scale that holds the sins so that the merits outweigh the sins.

The Gemara explains the connection between the two disputes: Rabba holds in accordance with the opinion of Rabbi Elazar, and therefore he interprets the verse as saying that God is benevolent because He discards one’s judgments, i.e., sins, by throwing them to the great deep, thereby allowing his merits to outweigh his sins. And Rav Yehuda holds in accordance with the opinion of Rabbi Yosei, son of Rabbi Ḥanina, and therefore he interprets the verse to mean that God lifts the side of merits as high as the mighty mountains, and were it not for this act of benevolence no one could stand before God’s judgments, which are like the great deep.

MISHNA: No fewer than four full thirty-day months may be established during the course of a year, and it did not seem appropriate to establish more than eight. The two loaves that are brought to the Temple on Shavuot are eaten by the priests not before the second and not after the third day from when they were baked. The shewbread is eaten not before the ninth day from when it was baked, which is the situation in a regular week when the bread is baked on Friday and eaten on the following Shabbat; and not after the eleventh day, when the two Festival days of Rosh HaShana occur on Thursday and Friday, as the shewbread is baked on Wednesday and not eaten until the following Shabbat.

A minor boy is not circumcised before the eighth day after his birth and not after the twelfth day. Normally a newborn is circumcised on his eighth day. If he was born during twilight, which an uncertain period of day or night, he is circumcised on what would be the eighth day of his birth if he is was born at night, which is the ninth day if he was born during the day. If he was born during twilight on Shabbat eve, the circumcision cannot be performed on Friday, as he might have been born on Shabbat and therefore Friday is only the seventh day. And the circumcision cannot be on Shabbat, as perhaps he was born on Friday and only circumcision performed on the eighth day overrides Shabbat. Therefore, it is postponed until after Shabbat. If two days of Rosh HaShana occur on Sunday and Monday, the circumcision is postponed until Tuesday, the twelfth day after birth.

GEMARA: The Gemara asks: What is the meaning of the statement of the mishna that it did not seem appropriate to establish more than eight? Rav Huna says: It did not seem appropriate to the Sages to extend more than eight months in a year and establish them as full, thirty-day months. The Gemara asks: What is different about nine months, in that the Sages did not deem it appropriate to establish that many full months in one year? Apparently, the Sages were concerned that if so, i.e., if there were that many full months,