1) SEVEN DAYS OF NIDAH FOLLOWED BY ELEVEN DAYS OF ZIVAH
QUESTION: The Gemara discusses the eleven days of Zivah that follow the seven days of Nidah. The Rishonim explain that, mid'Oraisa, whenever a woman sees blood, she must count seven days of Nidah. Any blood she sees after those seven days, within a period of eleven days, is considered the blood of Zivah. This eleven-day period begins only after a seven-day period of Nidah. This is clear from a number of Sugyos in the Gemara.
The RAMBAM (Hilchos Isurei Bi'ah 6:4-6) writes that a woman always counts seven days of Nidah followed by eleven days of Zivah. During the seven days of Nidah, any blood she sees is considered Dam Nidah. During the eleven days of Zivah, any blood she sees is considered Dam Zivah. During the eleven-day period, she can become a Zavah whether or not she was previously a Nidah, and during the seven-day period she can become a Nidah whether or not she was previously a Zavah. She goes through consistent and consecutive periods of Nidah (seven days) and Zivah (eleven days). According to the Rambam, a woman must keep track of her count of seven days of Nidah, eleven days of Zivah, seven days of Nidah, eleven days of Zivah, and so on, perennially.
The Rambam's opinion seems to contradict many Sugyos that imply that the state of Nidah starts only after she becomes Tahor from her Zavah state. The Gemara clearly states that a Zavah cannot see blood that will make her a Nidah (37b). How does the Rambam understand these Sugyos?
ANSWER: The NETZIV (here, and in his notes to the She'iltos, Tazria 86:4) explains in the following manner. The RIF cites the verses from which we learn the count of seven days and eleven days, in accordance with the opinion of Rebbi Akiva who learns that the source of the eleven-day count is a verse. The Rif adds that we do not rule like this opinion, but rather like Rebbi Elazar ben Azaryah, who says that the eleven-day count is derived from a Halachah l'Moshe mi'Sinai.
Why does the Rif bother to explain the different opinions regarding the source for the eleven-day count? The Rif writes Halachic conclusions; in what way is the source for the eleven-day count relevant to the Halachah?
The Netziv answers that the source is relevant to Halachah in the following way. If the eleven-day count is derived from a verse, then the days of Zivah will be only the days immediately after a woman actually saw Dam Nidah and counted seven days, as is clear from the verse. If the woman did not become a Nidah, she does not count eleven days. This is the opinion of Rebbi Akiva according to the Rif. All of the Sugyos throughout the Gemara that are not in accordance with the Rambam's ruling follow the opinion of Rebbi Akiva.
In contrast, Rebbi Elazar ben Azaryah learns that the source for the eleven-day count is a Halachah l'Moshe mi'Sinai, and that the Halachah l'Moshe mi'Sinai teaches that the count is always a consistent, alternating count of seven days followed by eleven days. The Rambam rules like the Rif, in accordance with the opinion of Rebbi Elazar ben Azaryah.
2) THE JOY OF LEARNING TORAH
AGADAH: Maseches Nidah, and all of Shas, concludes with the teaching of Tana d'Vei Eliyahu who says, "One who learns Halachos every day is guaranteed a portion in the World to Come." RASHI (DH Halachos) writes that "Halachos" refers to the Halachos l'Moshe mi'Sinai -- the Mishnayos and Beraisos.
The CHIDUSHEI CHASAM SOFER explains the special connection between learning Halachos and earning a portion in Olam ha'Ba based on the Gemara in Shabbos (30b). The Gemara there states that the Shechinah dwells only among the Simchah of performing a Mitzvah. Rav Yehudah there adds that "similarly, for a word of Halachah [Simchah is necessary]." Rashi there explains that before one learns Halachah, he should begin with words that put him into a happy mood.
The Chasam Sofer explains that since Simchah is necessary for learning Halachah, it follows that one who studies Halachos every day certainly must be happy every day. He will be "among the insulted who does not insult" (Shabbos 88b), he will be happy with Hash-m all of his life, and he will learn Torah with the trait of joy and contentment. A person like that certainly will merit Olam ha'Ba.
The Chasam Sofer explains another Gemara in this manner. The Gemara in Megilah (28b) relates that Reish Lakish was once walking along the way when he came upon a large expanse of water blocking his route. Somebody came along and offered to carry Reish Lakish on his shoulders across the water. While they were going through the water, Reish Lakish discovered that the person carrying him was learned in four Sedarim of the Mishnah. Reish Lakish was distressed that he had benefited from the services of one who learns "Halachos." Reish Lakish's escort, however, protested that it was his desire to serve Reish Lakish. Reish Lakish agreed to let him continue carrying him on the condition that he allow Reish Lakish to teach him two Halachos (so that he would be considered Reish Lakish's student and would be permitted to serve Reish Lakish in such a manner). The first Halachah that Reish Lakish taught was the statement of Rebbi Zeira, that the daughters of Yisrael are stringent upon themselves to wait seven Tahor days even when they see a drop of blood the size of a mustard seed. The second Halachah that Reish Lakish taught him was the statement that everyone who learns Halachos is guaranteed to have a portion in Olam ha'Ba.
As the Chasam Sofer explains, Reish Lakish discerned that his porter was a very humble person who did not consider himself important, even though he had learned four Sedarim of Mishnah, since he had offered to carry Reish Lakish, and since he did not dress like a Talmid Chacham. This trait of humility is characteristic of wise people who view their good deeds as unworthy of reward, and who view even the slightest transgression that they might have committed in their youth as severe and constantly requiring atonement. Even though this outlook is proper for Tzadikim and Chachamim, one should still be careful not to let it lead to melancholy. One's heart should always be happy with Hash-m at all times.
This is alluded to in the Halachah that the daughters of Yisrael are stringent upon themselves even with regard to the smallest transgression, symbolized by a drop of blood the size of a mustard seed. The seven Tahor days that she observes for such a small drop represents the seventy years of a person's life which the Tzadik spends in continual repentance for the smallest misdeed of his youth.
Reish Lakish said to his porter, "There is no doubt that you are one of these Tzadikim. However, you must be aware of the fact that one who learns Halachos every day must certainly be happy with a good heart, and thus he must be worthy of Olam ha'Ba, because the Shechinah dwells only on a person who has the Simchah of Mitzvos." (D. BLOOM)
3) ONE WHO LEARNS HALACHOS EVERY DAY
QUESTION: The Gemara at the end of Nidah quotes Tana d'Vei Eliyahu who says, "One who learns Halachos every day is guaranteed a portion in the World to Come."
Until now, the Gemara has been discussing the source for the eleven days of Zivah. In what way is the statement of Tana d'Vei Eliyahu related to the subject matter at hand?
ANSWERS:
(a) RAV DAVID LURIA (the Radal) of Bichov explains that in numerous places the Gemara uses the word "Halachos" to refer to teachings of the Mishnayos, in contrast to teachings of the Gemara (see RASHI, end of Megilah 26b). Tana d'Vei Eliyahu is encouraging us to learn the remainder of the Mishnayos of Seder Taharos even though we have no Gemara to explain them to us.
(b) The BE'ER SHEVA points out that there is only one other place in Shas where this statement is repeated -- in Megilah (28b). There, too, it immediately follows a discussion pertaining to the laws of the Yemei Nidah and Yemei Zivah of a woman. It is evident that there is some connection between these laws and this statement of Tana d'Vei Eliyahu. What is that connection?
The Mishnah in Avos (3:18) teaches, "Even the laws of bird-offerings and the laws concerning the beginning of the Nidah and Zivah cycles are essential Halachos of the Torah ('Gufei Halachos')" (as explained in Chagigah 11b; see Insights to Erchin 8:1). The NIMUKEI HA'GRIV explains that this Mishnah in Avos is the reason for why the Gemara here and in Megilah conclude with the statement that one who learns Halachos every day will merit a portion in the World to Come. The Gemara is teaching that even the study of Halachos such as the laws regarding the beginning of the Nidah and Zivah cycles -- which seem to be merely mathematical calculations -- guarantees a person a portion in the World to Come.
HADRAN ALACH MASECHES NIDAH, U'SELIKA LAH KULEI SHAS

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