ישבה לה ולא בדקה שגגה נאנסה הזידה ולא בדקה טהורה

If a woman sat and did not examine herself every morning and evening to determine whether she emitted blood and is impure, it makes no difference whether she failed to examine herself unwittingly or due to circumstances beyond her control, or even if she acted intentionally and did not examine herself; she remains ritually pure. She is rendered impure only if she examined herself and was found to have emitted blood.

הגיע שעת וסתה ולא בדקה הרי זו טמאה רבי מאיר אומר אם היתה במחבא והגיע שעת וסתה ולא בדקה הרי זו טהורה מפני שחרדה מסלקת את הדמים

By contrast, if the time of her menstrual cycle arrived, when she is required to examine herself, and she did not examine herself, that woman is ritually impure, as it is typical for a woman to discharge blood at that time. Rabbi Meir says: If a woman was in hiding from danger, and the time of her menstrual cycle arrived and she did not examine herself on that day, that woman is pure, because fear drives away blood. There is therefore no concern that she might have emitted blood.

אבל ימי הזב והזבה ושומרת יום כנגד יום הרי אלו בחזקת טומאה

But with regard to the seven clean days of the zav and the zava, and with regard to a woman who observes a clean day for a day she experiences a discharge during her days of ziva, if she fails to examine herself on those days, these women have a presumptive status of ritual impurity, as they already experienced a discharge.

גמ׳ למאי הלכתא אמר רב יהודה לומר שאינה צריכה בדיקה והא מדקתני סיפא ישבה ולא בדקה מכלל דלכתחלה בעיא בדיקה

GEMARA: The mishna teaches that throughout the eleven days of ziva that follow the seven days of menstruation, a woman has the presumptive status of ritual purity. The Gemara asks: With regard to what halakha is this stated? Rav Yehuda says: This serves to say that she does not require an examination during these days. The Gemara objects: But from the fact that the latter clause teaches: If she sat and did not examine herself she remains ritually pure, it can be inferred that she requires examination ab initio.

סיפא אתאן לימי נדה והכי קאמר כל אחד עשר בחזקת טהרה ולא בעיא בדיקה אבל בימי נדתה בעיא בדיקה ישבה ולא בדקה שגגה נאנסה הזידה ולא בדקה טהורה

The Gemara explains: In the latter clause we arrive at the case of a woman who is in the days of menstruation, not in the days of ziva. And this is what the mishna is say ing: For all the eleven days of ziva that follow the days of menstruation, a woman has the presumptive status of ritual purity and she does not require examination. But during the days of her menstruation she requires examination. Nevertheless, if she sat and did not examine herself, whether unwittingly or due to circumstances beyond her control, or even if she acted intentionally and did not examine herself, she remains ritually pure.

רב חסדא אמר לא צריכא אלא לרבי מאיר דאמר אשה שאין לה וסת אסורה לשמש הני מילי בימי נדתה אבל בימי זיבתה בחזקת טהרה קיימא

Rav Ḥisda said a different answer: The first clause of the mishna is necessary only for the opinion of Rabbi Meir, who said: With regard to a woman who does not have a fixed menstrual cycle, she is forbidden to engage in intercourse, lest she emit blood during intercourse. The mishna is teaching that this statement applies only during the days of her menstruation, but during the days of her ziva even Rabbi Meir concedes that she stands in her presumptive status of purity and may engage in intercourse with her husband.

אי הכי אמאי אמר רבי מאיר יוציא ולא יחזיר עולמית דלמא אתיא לקלקולא בימי נדה

The Gemara asks: If so, that even according to Rabbi Meir there are days in which a woman who does not have a fixed menstrual cycle is permitted to engage in sexual intercourse with her husband, why did Rabbi Meir say that her husband must divorce her and he may never take her back, even if she eventually develops a fixed menstrual cycle? Let them engage in intercourse during the eleven days of ziva. The Gemara answers: He must divorce her lest the matter lead to failure during the days of menstruation, i. e., in case they come to engage in intercourse during the days of menstruation, when she might experience regular menstrual bleeding.

הא מדקתני סיפא הגיע שעת וסתה ולא בדקה מכלל דבאשה שיש לה וסת עסקינן חסורי מחסרא והכי קתני כל אחד עשר בחזקת טהרה ושריא לבעלה ובימי נדה אסורה

The Gemara objects: But from the fact that the latter clause teaches: If the time of her menstrual cycle arrived and she did not examine herself, that woman is ritually impure, it can be inferred that we are dealing with a woman who has a fixed menstrual cycle. The Gemara explains: The mishna is incomplete and this is what it is teaching: For all the eleven days of ziva that follow the days of menstruation, a woman has the presumptive status of ritual purity and she is permitted to her husband, but during the days of menstruation she is prohibited to her husband.

במה דברים אמורים באשה שאין לה וסת אבל יש לה וסת מותרת וצריכה בדיקה ישבה ולא בדקה שגגה נאנסה הזידה ולא בדקה טהורה הגיע שעת וסתה ולא בדקה טמאה

In what case is this statement said? In the case of a woman who does not have a fixed menstrual cycle, where there is a concern she might experience bleeding during any of the days of menstruation. But in the case of a woman who has a fixed menstrual cycle, she is permitted to engage in sexual intercourse with her husband, and she requires examination. Nevertheless, if she sat and did not examine herself, whether unwittingly or due to circumstances beyond her control, or even if she acted intentionally and did not examine herself, she remains ritually pure. If the time of her menstrual cycle arrived and she did not examine herself, she is impure.

הא מדסיפא רבי מאיר רישא לאו רבי מאיר כולה רבי מאיר היא והכי קאמר אם לא היתה במחבא והגיע שעת וסתה ולא בדקה טמאה שרבי מאיר אומר אם היתה במחבא והגיע שעת וסתה ולא בדקה טהורה שחרדה מסלקת את הדמים

The Gemara objects: But from the fact that the last clause is in accordance with the opinion of Rabbi Meir, it can be inferred that the first clause is not in accordance with the opinion of Rabbi Meir. The Gemara explains that the entire mishna is in accordance with the opinion of Rabbi Meir, and this is what it is say ing: If she was not in hiding and the time of her menstrual cycle arrived and she did not examine herself, she is impure, as Rabbi Meir says: If a woman was in hiding and the time of her menstrual cycle arrived and she did not examine herself, she is pure, as fear drives away blood.

רבא אמר לומר שאינה מטמאה מעת לעת

Rava says a different explanation of the first clause of the mishna: The mishna is coming to say that if a woman experiences bleeding during the eleven days of ziva, as she previously had the presumptive status of purity she does not impart impurity retroactively for a twenty-four-hour period to any ritually pure items she touched. It is assumed that she did not emit any blood before this emission.

מיתיבי הנדה והזבה והשומרת יום כנגד יום והיולדת כולן מטמאות מעת לעת תיובתא

The Gemara raises an objection from a baraita: With regard to a menstruating woman, and a zava, and a woman who observes a day for a day, and a woman who gave birth, they all impart impurity retroactively for a twenty-four-hour period. A woman who observes a day for a day is one who experiences bleeding for one or two days during her days of ziva, and the baraita teaches that even such a woman imparts impurity retroactively for a twenty-four-hour period. If so, this is a conclusive refutation of Rava’s explanation.

רב הונא בר חייא אמר שמואל לומר שאינה קובעת לה וסת בתוך ימי זיבתה אמר רב יוסף לא שמיע לי הא שמעתתא

Rav Huna bar Ḥiyya says another explanation of the first clause of the mishna in the name of Shmuel: The mishna is coming to say that a woman does not fix a menstrual cycle for herself during the days of her ziva. In other words, a sighting during these days does not combine with sightings during the previous two periods of ziva to establish a fixed menstrual cycle. The Gemara relates that this statement was recited before Rav Yosef, who said: I did not hear this halakha from Shmuel.

אמר ליה אביי את אמרת ניהלן ואהא אמרת לן היתה למודה להיות רואה יום חמשה עשר (יום) ושינתה ליום עשרים זה וזה אסורין לשמש שינתה פעמים ליום עשרים זה וזה אסורין

Abaye said to him: But you yourself told us this halakha, and it was with regard to that mishna you told it to us, as we learned in a mishna (63b): If the woman was accustomed to see an emission of blood on the fifteenth day, so that this was her fixed menstrual cycle, and she deviated from her cycle to see an emission on the twentieth day, then on both this day, the fifteenth, and that day, the twentieth, it is prohibited for her to engage in sexual intercourse due to the concern that she might have an emission on either day. If she deviated from her cycle twice, to see an emission on the twentieth day, then on both this day and that day it is prohibited for her to engage in intercourse. If she deviates a third time to see on the twentieth she has established for herself a new fixed menstrual cycle.

ואמרת לן עלה אמר רב יהודה אמר שמואל לא שנא אלא חמשה עשר לטבילתה שהן עשרים ושנים לראיתה דהתם בימי נדתה קאי לה אבל חמשה עשר לראיתה דבימי זיבתה קאי לא קבעה

Abaye continues: And you said to us with regard to this mishna that Rav Yehuda said that Shmuel said: They taught this halakha only with regard to a woman who normally experiences bleeding fifteen days from her immersion, which are twenty-two days from her sighting of menstrual blood. This means that there, she stands in her days of menstruation. But if she normally experiences bleeding fifteen days from her sighting of menstrual blood, so that she stands in her days of ziva, she has not fixed a menstrual cycle, and the previous cycle is uprooted even if she deviates from it only once.

אמר רב פפא אמריתא לשמעתא קמיה רב יהודה מדסקרתא מקבע לא קבעה מיחש מהו דניחוש לה

§ With regard to the ruling that a woman’s menstrual cycle cannot be fixed during her days of ziva, Rav Pappa said: I said this halakha before Rav Yehuda of Diskarta, and I asked him for a clarification of the following matter: Granted, she does not fix a menstrual cycle during the days of ziva, and there is no need for three deviations to uproot her cycle; rather, it is uprooted by even one deviation. But what is the halakha with regard to whether we should be concerned that she might experience bleeding? In other words, if she normally experiences bleeding on a particular day during her days of ziva, must she avoid engaging in sexual intercourse with her husband on that day out of concern that she might emit blood?

אישתיק ולא אמר ליה ולא מידי אמר רב פפא נחזי אנן היתה למודה להיות רואה ליום חמשה עשר ושינתה ליום עשרים זה וזה אסורין

Rav Yehuda of Diskarta was silent and did not say anything to Rav Pappa. Therefore, Rav Pappa said: Let us see and try to resolve this ourselves. The mishna cited above states: If the woman was accustomed to see an emission of blood on the fifteenth day, and she deviated from her cycle to see an emission on the twentieth day, then on both this day and that day it is prohibited for her to engage in sexual intercourse.