1) COUNTING THE DAYS AND WEEKS OF THE "OMER"
OPINIONS: Abaye and Ameimar argue about how to count the Omer. Abaye says that the Mitzvah is to count both the number of weeks and the number of days. This was the practice of the Chachamim of the Beis ha'Midrash of Rav Ashi. Ameimar disagrees and says that only the days need to be counted. He explains that since the counting of the Omer in the absence of the Beis ha'Mikdash is merely a remembrance for the Beis ha'Mikdash, it suffices to count only the days.
What is the underlying point of dispute between Abaye and Ameimar?
(a) The RAMBAM (Hilchos Temidin u'Musafin 7:24) writes that the Mitzvah of counting the Omer applies "in every place and at all times." Since the Rambam writes that it applies "at all times," this implies that the Rambam maintains that it is a Mitzvah d'Oraisa to count the Omer even when there is no Beis ha'Mikdash. What is the source for the Rambam's view?
1. The KESEF MISHNEH and MAHARI KURKUS explain that the Rambam understands that Abaye and Ameimar disagree about whether the Mitzvah of Sefiras ha'Omer is a Torah obligation nowadays (in the absence of the Beis ha'Mikdash). Abaye maintains that it is a Torah obligation, and, therefore, one must mention both the weeks and the days. Ameimar maintains that the Mitzvah today is only mid'Rabanan, an enactment made to commemorate the Mitzvah d'Oraisa that applies when the Beis ha'Mikdash is standing, and therefore only the days need to be counted. The Rambam rules like Abaye and Rav Ashi, and therefore he says that this Mitzvah applies "at all times," whether or not there is a Beis ha'Mikdash.
2. RAV CHAIM SOLOVEITCHIK (Chidushei ha'Shas, #343) explains that the Rambam understands that both Abaye and Ameimar maintain that the Mitzvah of Sefiras ha'Omer is mid'Rabanan, because they maintain that the Kedushah of the Beis ha'Mikdash became annulled when the Beis ha'Mikdash was destroyed (see Megilah 10a). However, the Rambam rules that the Kedushah endures until today. Although Korbanos are not offered today for other reasons (see Insights to Shevuos 16:1), the Mitzvah of Sefiras ha'Omer is mid'Oraisa since the Kedushah still exists. Therefore, the Rambam rules that the Mitzvah today is a Torah obligation and applies "at all times."
(b) TOSFOS (DH Zecher) and the RAN in Pesachim (28a of the pages of the Rif) rule that the Mitzvah of Sefiras ha'Omer today is mid'Rabanan. (This is also the way the TUR and SHULCHAN ARUCH (OC 489) rule.) They understand that this is the view of all of the Amora'im in the Gemara as well. The dispute between Abaye and Ameimar is whether one should count only the days because the Mitzvah is only mid'Rabanan, or whether one should do the Mitzvah as it was done when it was a Torah obligation.
(c) RABEINU YERUCHAM (Nesiv Chamishi #4) writes that the Mitzvah of Sefiras ha'Omer today is mid'Oraisa, and that this is the view of all of the Amora'im in the Gemara. He explains that when Ameimar says that the Mitzvah is only a "remembrance" of the Beis ha'Mikdash, he means that when the Beis ha'Mikdash was standing, the Mitzvah d'Oraisa was to count the days and the weeks, and when the Beis ha'Mikdash is not standing, the Mitzvah d'Oraisa is to count only the days.
The OR SAME'ACH (Hilchos Temidin u'Musafin 7:22) says that this view is also found in the IGROS HA'RAMAH. He explains that the Torah attaches the Mitzvah of counting weeks to the bringing of the Omer offering when it says, "Begin to number the seven weeks from such time as you begin to put the sickle to the grain" (Devarim 16:9). However, the Mitzvah to count the days is not conditional on the bringing of the Omer offering. (Y. MONTROSE)

66b----------------------------------------66b

2) GRAIN PILED BY A NOCHRI
OPINIONS: The Gemara discusses whether or not a Nochri who piles grain or smoothes a pile of grain (and thereby performs the final act of harvesting the grain, which normally makes the grain subject to the obligation to separate Terumos u'Ma'aseros; see RASHI DH Miru'ach) exempts the pile of grain from Ma'aser. The Gemara says that this is the subject of a dispute among the Tana'im.
In what case does the dispute apply? Does the Gemara refer to a case in which a Nochri piles his own grain, or even to a case in which he piles the grain of a Jew?
(a) RABEINU GERSHOM writes that the Gemara refers to a case in which "a Nochri had a heap of grain and he smoothed over the grain," implying that the Nochri smoothed over his own grain. When the grain is that of a Jew, the harvest is still obligated in Ma'aser according to Torah law. This is also the opinion of the RITVA and ME'IRI in Gitin (47a), as well as many other Rishonim.
(b) The RAMBAM (Hilchos Terumos 1:13) rules that if a Nochri finishes the harvest of a Jew's grain, it is exempt from Ma'aser according to Torah law (although it might be obligated mid'Rabanan). The KESEF MISHNEH writes in the name of the MAHARI KURKUS that the source for the Rambam's statement is the verse, "Degancha" -- "your grain" (Devarim 18:4), from which the Gemara here derives that only the grain of a Jew is obligated and not the grain of Nochrim. The Rambam learns that this includes grain that Nochrim "finished." This is also the opinion of the SHITAH MEKUBETZES (67a, #1), TOSFOS RID in Gitin (47a), and others.
Rabeinu Gershom's opinion seems to be the most straightforward explanation. How does the Rambam know that the Gemara refers even to a case in which the Nochri "finishes" the produce of a Jew?
The KEREN ORAH explains that the Rambam learns this way because he rules that grain bought from a Nochri after its processing has been finished is exempt from Ma'aser, since it is "Laku'ach" (purchased grain). Once the law is that grain bought from a Nochri is exempt from Ma'aser, why is a special verse of "Degancha" needed to teach that grain finished in his possession is exempt from Ma'aser? It must be that the case of a Nochri who smoothes a pile of grain refers to a case in which he smoothes the grain of a Jew. The verse is teaching that even in such a case, where the grain belongs to a Jew, the grain is exempt from Ma'aser according to Torah law.
The Keren Orah, however, asks that this does not seem to be the intention of the Gemara. The Gemara later (67a) equates a Nochri's separating of Chalah from dough to his act of finishing the grain. No one says that when a Nochri kneads the dough of a Jew, the dough is exempt from Chalah. The SHULCHAN ARUCH (YD 330:1) rules that there is no Halachic relevance to who kneads the dough. Rather, the obligation of Chalah depends on who owns the dough. The Keren Orah also questions the Rambam's view from the Gemara earlier that discusses Miru'ach of Hekdesh, which obviously refers to grain that is in the possession of Hekdesh. Accordingly, "Miru'ach Oved Kochavim" also should refer to grain that is owned by a Nochri.
HALACHAH: The opinion of the Rambam seems to present a problem for the practice of separating Ma'aser from produce in Eretz Yisrael today. According to the Rambam, one would have to be very careful to ensure that produce "finished" by Nochri workers (which is not obligated in Ma'aser) is not used as Ma'aser for produce "finished" by Jewish workers (which is obligated in Ma'aser). The DERECH EMUNAH (Hilchos Terumos 1:149) quotes the CHAZON ISH who says that because the obligation to separate Terumah today is only mid'Rabanan, we may rely on the opinion of the Rishonim who argue with the Rambam's ruling that all Jewish-owned produce is obligated in Terumah and Ma'aser, even if the produce was "finished" by Nochri workers. (Y. MONTROSE)

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