1) HALACHAH: THE LAW OF "VESES"
HALACHAH: The Gemara discusses the law of Veses. This refers to the obligation for a woman to examine herself with a proper Bedikah on the day of the month on which she normally experiences her flow of Dam Nidah, in order to ensure that she is still Tahor. The Gemara records various opinions about whether this requirement is mid'Oraisa ("Vestos d'Oraisa") or mid'Rabanan ("Vestos d'Rabanan").
What is the Halachah?
(a) Most Rishonim maintain that Vestos are mid'Rabanan. TOSFOS (DH v'Rav Nachman) writes that this is the Halachah because Rav Nachman bar Yitzchak (a later Amora) says that Rav maintains that Vestos are mid'Rabanan (and the Halachah follows Rav, not Shmuel, in questions of Isur v'Heter). Tosfos says that this is also the opinion of the SHE'ILTOS D'RAV ACHAI GA'ON and the RACH.
(b) The ME'IRI quotes some Rishonim who maintain that Vestos are mid'Oraisa. Some attribute this opinion to TOSFOS in Pesachim (72b, DH Samuch) and RABEINU TAM cited by Tosfos in Yevamos (62b, DH Chayav). They maintain that the prohibition to be with one's wife "Samuch l'Vestah," near the time of her Veses, is mid'Oraisa. This also seems to be the intention of the Gemara in Yevamos (62b) which derives the prohibition from the verse, "v'Hizartem Es Bnei Yisrael mi'Tum'asam" -- "and you will separate Bnei Yisrael from their Tum'ah" (Vayikra 15:31). It is logical to assume that since they maintain that the prohibition of Samuch l'Vestah is mid'Oraisa, it must be that the law of Vestos is also mid'Oraisa. Since the Torah forbids being with one's wife at the time of Samuch l'Vestah because she is likely to become a Nidah, certainly the prohibition to be with one's wife during her Veses itself should be mid'Oraisa.
However, the NODA B'YEHUDAH (YD 1:55) says that it is possible that the Isur of Samuch l'Vestah is mid'Oraisa while the law of Veses itself is only mid'Rabanan. He cites the Gemara in Gitin (28b) which teaches that the Halachah suspects, under certain circumstances, that a person might die, but the Halachah does not suspect that someone has already died. What is the logic behind this? The difference is based on the Chazakah (status) of the person. When one has a Chazakah that he is alive, the Halachah does not suspect that he might have died, because this suspicion opposes his present status. In contrast, if, due to circumstances, there is reason to suspect that one might die, this suspicion does not contradict a previous status, because the doubt is whether or not the person will still be alive in the near future.
Similarly, the prohibition of the Veses is weak (according to the opinion that it is mid'Rabanan), because once a woman passes her Veses and does not become a Nidah, it makes sense that she retains her previous status of not being a Nidah. There is no concern that she became a Nidah already and did not know it, just as there is no concern that a person already died, since such a concern is contrary to a Chazakah. The Torah therefore does not forbid her during the actual Veses. However, immediately before she expects to become a Nidah, there should be a concern that she is about to become a Nidah. Accordingly, it is possible that the opinion that Veses is mid'Rabanan maintains that the Isur of Samuch l'Vestah is prohibited mid'Oraisa. This approach is also expressed by the CHASAM SOFER (Teshuvos, YD 170 and 179).
According to the Noda b'Yehudah's explanation, it is no longer clear that Tosfos in Pesachim (72b, DH Samuch) and Rabeinu Tam in Yevamos (62b, DH Chayav) disagree with the other Rishonim who maintain that Vestos are mid'Rabanan (see also Insights to Shevuos 18b). The ARUCH HA'SHULCHAN (YD 184) explicitly states that this indeed is the opinion of Rabeinu Tam, among other Rishonim. (Y. MONTROSE)
2) TWO CLOTHS
OPINIONS: The Mishnah records a dispute between Beis Shamai and Beis Hillel regarding how many cloths are necessary for the Bedikos of Tashmish. Beis Shamai requires two cloths for each act of Tashmish, while Beis Hillel rules that two cloths are enough for the entire night. What is done with these two cloths?
(a) RASHI explains that the two cloths are needed for Bedikos before and after each act of Tashmish. Beis Shamai requires them for each act of Tashmish of the night, while Beis Hillel asserts that one is used before the first Tashmish and the second is used after the last Tashmish.
(b) TOSFOS (DH Beis Shamai) and the other Rishonim suggest that both cloths are needed for Bedikos after Tashmish, but one is for the husband's Bedikah and the other is for the wife's Bedikah.

16b----------------------------------------16b

3) THE "BEDIKOS" OF BEIS HILLEL
QUESTION: Rebbi Zeira states that a meticulously scrupulous person should perform a Bedikah after every act of Tashmish. What is the source for this ruling? According to Beis Hillel, no Bedikah is required until after the last act of Tashmish of the night. Does Rebbi Zeira rule like Beis Shamai in this regard?
ANSWERS:
(a) RASHI understands that Rebbi Zeira infers from the words of Beis Hillel that there it is a Midas Chasidus to examine for blood between each act of Tashmish.
(b) The RAMBAM (Hilchos Isurei Bi'ah 4:17) writes that even Beis Hillel agrees that one must examine after each act of Tashmish. He argues with Beis Shamai only with regard to whether the same cloth may be used for all of the Bedikos.
(c) TOSFOS (DH Beis Shamai) maintains that even Beis Hillel agrees that one must examine both before and after every act of Tashmish. According to Beis Shamai, they must prepare enough cloths in order for both of them to have two cloths to use after every act of Tashmish. According to Beis Hillel, the same cloth may be used for all of the Bedikos after Tashmish.
4) IS A PERSON'S INTELLIGENCE IN THE HANDS OF HASH-M?
QUESTION: The Gemara states that the angel who is in charge of pregnancies brings the drop of seed before Hash-m and says, "What should this be -- a strong person or a weak person, a smart person or a stupid person, a poor person or a rich person?" The Gemara points out that the angel does not ask whether the person will be evil or righteous. This is in accordance with the statement of Rebbi Chanina, who says that everything is in the hands of Hash-m except Yir'as Shamayim, the fear of Hash-m.
The RAMBAM (Hilchos Teshuvah 5:2), however, writes something apparently contrary to the Gemara. He writes, "Do not think... that Hash-m decrees on a person from the beginning of his creation to be righteous or evil. This is not so. Rather, everyone can be a Tzadik like Moshe Rabeinu, or a Rasha like Yarav'am, or wise or foolish, or kind or cruel...." The HAGAHOS MAIMONIYOS asks that the Rambam's statement that a person can choose whether or not to be wise or foolish seems contrary to the Gemara here which says that Hash-m decides before a person's birth whether he will be smart or stupid. How can the Rambam say that this is in the hands of the person?
ANSWERS:
(a) The HAGAHOS MAIMONIYOS answers that perhaps the Rambam uses the term "Sachal" instead of the Gemara's term "Tipesh," because he is referring to a different kind of fool. The Gemara is referring to being mentally intelligent or unintelligent, while the Rambam is referring to being clever with regard to Yir'as Shamayim or making oneself foolish not to fear Hash-m.
The KESEF MISHNEH disagrees with this answer. He argues that the word "Sachal" is not an appropriate expression to connote one who lacks Yir'as Shamayim.
(b) The Hagahos Maimoniyos quotes, in the name of his Rebbi, another answer in which he explains that the Gemara refers to having an intelligent nature, while the Rambam refers to a person's choice to use that intelligence (or not to use it). The CHOCHMAS BETZALEL here refers to the eighth chapter of SHEMONAH PERAKIM (the Rambam's introduction to Pirkei Avos) where the Rambam addresses this subject at length and gives an answer which can be interpreted to be the same as the answer of the Rebbi of the Hagahos Maimoniyos. (See Chochmas Betzalel for a lengthy discussion.)
(c) The MAHARATZ CHAYOS gives an answer based on the Rambam's own words in MOREH NEVUCHIM (3:54). The Rambam there discusses two types of wisdom: the wisdom of good manners, and the wisdom of knowing Hash-m. The former type of wisdom is comprised of the hereditary character traits (Techunos) that a person receives from his parents. The latter type of wisdom is determined by the degree to which a person strives to be a wise person. The Rambam in Hilchos Teshuvah means that a person can strive to be wise if he so chooses (similar to the earlier explanation of the Rebbi of the Hagahos Maimoniyos), while the Gemara refers to a person's inherent, hereditary character traits.
(RAV AVIGDOR MILLER zt'l used to say that a person must learn to identify which of his traits are Techunos and which are Midos. Techunos, he would explain, are hereditary and must be put to use for good purposes, since they generally will not change. For example, a person who has a Techunah to be active should work on applying that trait for good things, and he should not try to break his active nature. On the other hand, a bad Midah is not hereditary; rather, it is something that a person picked up at some point in his life. If one realizes that this tendency is leading him in the wrong direction, then he should not try to work with this Midah, but rather he should try to break his habit and change.) (Y. MONTROSE)

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