1) AGADAH: HOW MANY OF THE "ASERES HA'DIBROS" WERE HEARD DIRECTLY FROM THE VOICE OF HASH-M?
OPINIONS: Rebbi Yishmael states that the Jewish people at Sinai heard the first two commandments of the Aseres ha'Dibros ("Anochi Hash-m" and "Lo Yiheyeh Lecha") directly from Hash-m. Does this imply that they did not hear the other eight commandments from Hash-m, but from Moshe Rabeinu?
(a) The RAMBAM in MOREH NEVUCHIM (2:33) writes that this indeed is correct. He explains that even though the first two commandments were heard directly from Hash-m, the Jewish people did not understand the words; they could not comprehend where one word ended and the next began. Moshe Rabeinu clarified this for them. The Rambam explains that this is why the Torah repeatedly refers to the "Kol" ("sound" or "voice") that the Jewish people heard (see Devarim 4:12 and 5:19-20). They heard only the sound of the letters of the words, and they could not clearly discern the words until Moshe Rabeinu helped them. They did not hear the last eight commandments directly from Hash-m, but rather Moshe Rabeinu related them to the Jewish people as he heard them from Hash-m. (See RABEINU BACHYE to Shemos 20:1.)
(b) The RAMBAN (to Shemos 20:7) argues that the Jewish people definitely heard all ten of the Aseres ha'Dibros directly from Hash-m. He explains that the intention of Rebbi Yishmael is that the only commandments that the Jewish people heard and understood on the same level as Moshe Rabeinu were the first two. The rest of the commandments were also heard by the Jewish people directly from Hash-m, but they did not understand what they heard until Moshe Rabeinu explained it to them.
The Ramban explains that this is the meaning of the verse, "Moshe Yedaber, veha'Elokim Ya'anenu v'Kol" (Shemos 19:19). The verse is saying that Hash-m will be made to be heard by Moshe's explanation of the last eight commandments that they heard from Hash-m but did not understand.
(c) The BE'ER SHEVA quotes the MA'ASEI HASH-M who gives a different explanation. He says that the method of communication of Hash-m at Sinai was similar to that of a powerful and awesome king who gives orders to his servant. If he says all of his orders directly to his servant, then the servant will be very frightened. However, if the king gives the orders to a different party and intentionally lets the servant overhear the orders being given, this would be much less frightening. Similarly, after Hash-m said the first two Dibros directly to the Jewish people and they consequently became very frightened, Hash-m decided that in order to make the experience bearable for them He would say the rest of the Dibros as if He was speaking only to Moshe. The Jewish people heard but were not as frightened, and they understood all of the Aseres ha'Dibros clearly, with no need for explication. The difference was merely that the first two Dibros were said directly to them, while the rest of the Dibros were said directly to Moshe and overheard by them. (See also TORAH TEMIMAH to Shemos 20:2.) (Y. MONTROSE)
2) THE MITZVAS ASEH OF THE PROHIBITION OF NIDAH
OPINIONS: The Mishnah states that the obligation for a Tzibur to bring a Par He'elem Davar and the obligation for an individual to bring an Asham Taluy take effect upon the inadvertent transgression of both a Mitzvas Aseh (a positive commandment) of Nidah, and a Mitzvas Lo Sa'aseh (a negative commandment) of Nidah. The Mishnah explains that the Mitzvas Aseh is to separate from a woman who is a Nidah, and the Lo Sa'aseh is not to have relations with a Nidah.
What does the Mishnah mean when it says that the Mitzvas Aseh is "to separate from a Nidah"? It seems that the requirement to separate from a Nidah is merely another way of expressing the prohibition not to have relations with a Nidah!
(a) RASHI (DH Perosh) explains that this refers to the prohibition of having relations with a Nidah "Samuch l'Vestah." The Torah requires that one separate from his wife near the time that she expects to see Dam Nidah. The source for this Isur is the Gemara in Shevuos (18b) which quotes the verse, "And you will separate the Jewish people from their Tum'ah" (Vayikra 15:31). Rebbi Yoshiya derives from this verse that a man must separate from his wife when she is "Samuch l'Vestah." This is the positive commandment to separate from a Nidah.
The TOSFOS HA'ROSH and many others question Rashi's explanation. The Mishnah in Shevuos (14b) teaches that "this is the Mitzvas Aseh of Nidah for which one is obligated to bring a Korban: one who was having relations with a permitted woman who then told him that she just became Tamei; if he separates from her immediately, he transgresses, as he derives pleasure from the act of separating [immediately]" (see Insights to Shevuos 18a). "Rather, he must withdraw "b'Ever Mes." The Gemara there (17b) asks what the Mishnah means when it uses the words, "Zo Hi Mitzvas Aseh..." -- "this is the Mitzvas Aseh...." These words do not seem related to the previous statements in the Mishnah, and yet they imply that the Mishnah is now explaining something that it mentioned earlier. The Gemara answers that the Mishnah there is referring to the Mishnah here in Horayos, which says, "But one is Chayav for transgressing a Mitzvas Aseh and a Lo Sa'aseh of Nidah," and when the Mishnah there says, "This is the Mitzvas Aseh of Nidah...," it is explaining what this Mitzvas Aseh of Nidah is.
According to the Gemara in Shevuos, the case of the Mishnah here is the same as the one in the Mishnah in Shevuos, and the Mishnah there clearly describes the Mitzvas Aseh as the requirement to separate slowly from a Nidah! Why, then, does Rashi here say that the Mitzvas Aseh is the requirement to separate from one's wife "Samuch l'Vestah"?
Moreover, Rashi's explanation is based on the assumption that the prohibition of "Samuch l'Vestah" is mid'Oraisa. Most Rishonim, including the Tosfos ha'Rosh here, RASHBA, RITVA and others (see Yevamos 62b), explain that the Isur to be with one's wife when she is "Samuch l'Vestah" is d'Rabanan (see Insights to Shevuos 18b). This is consistent with the implication of the Gemara in Yevamos (62b) that says that a person must be with his wife before he departs on a trip, even if this falls out "Samuch l'Vestah," clearly implying that the Isur of "Samuch l'Vestah" is d'Rabanan, since the Rabanan have the right to override their own enactment where they see fit (see HE'EMEK SHE'EILAH 49:4).
The Acharonim (see MEROMEI SADEH and AHAVAS EISAN) explain the opinion of Rashi. The Mishnah in Shevuos states that the Mitzvas Aseh of Nidah is to separate from a Nidah "b'Ever Mes" and not immediately. This means that the positive Mitzvah in that Mishnah is not to separate immediately, but rather to wait. How is this consistent with the Mishnah here, which says that the Mitzvah is "to separate" from a Nidah? The Gemara in Shevuos (18b) seems consistent only with the opinion of Abaye, who says that one who has forbidden relations "b'Ever Mes" is considered to have transgressed the prohibition of that forbidden union. It is logical that the Torah would tell a man who must withdraw in such a manner to be "Perosh Min ha'Nidah," meaning to separate from a woman who bears the regular prohibition of Nidah in this situation. However, according to Rava, who says that one who has forbidden relations "b'Ever Mes" does not transgress that prohibition, once the man is "b'Ever Mes" he no longer is involved in the Torah prohibition of actual relations with a Nidah. It is logical that if the Torah did not directly forbid relations in this manner (of "b'Ever Mes"), then it certainly did not give a direct Mitzvah saying that he must withdraw at this point! Therefore, Rashi learns that the Gemara in Shevuos that states that this is the Mitzvas Aseh of Nidah mentioned in the Mishnah here in Horayos must be following the view of Abaye. When Rashi here says that the Mitzvas Aseh is that of "Samuch l'Vestah," he is explaining the case according to Rava.
The Ahavas Eisan shows that the Yerushalmi (2:5) explicitly supports Rashi's opinion. The Yerushalmi states, "What is the positive commandment of Nidah? Rebbi Avin says, 'And you will separate the Jewish people from their Tum'ah' (Vayikra 15:31)." This is also the source of the prohibition of "Samuch l'Vestah," as mentioned above.
(b) The TOSFOS HA'ROSH, RAMBAM (in Perush ha'Mishnayos), and most other Rishonim learn like the straightforward explanation implied by the Gemara in Shevuos (14b and 18b). The case is one in which a man was informed, during relations with a permitted woman, that she had just experienced her Dam Nidah; he must not withdraw immediately, but rather he must wait and withdraw "b'Ever Mes." (Y. MONTROSE)