1) THE TORAH CALLS FOWL "MEAT"
QUESTION: The Mishnah states that one who makes a Neder not to eat meat is allowed to eat the flesh of fish and Kosher locusts. RASHI (DH ha'Noder) explains that what is included in a person's Neder depends on the popular usage of the word that he used. The Mishnah is teaching that people do not refer to fish and locusts as "Basar," meat.
The Gemara infers from the Mishnah that one who makes a Neder not to eat meat is prohibited from eating the meat of birds. This follows the view of Rebbi Akiva, who maintains that a specific object is considered to be included in a general term if a Shali'ach -- who is commanded, with the general term, to bring something -- would ask whether he should bring the specific object. Since a Shali'ach would ask whether he should bring fowl when commanded to bring "meat," fowl therefore is included in the term "meat."
The RAMBAM (Hilchos Nedarim 9:6) rules, based on this, that in a place where a Shali'ach who is told to buy "meat" might return with fish, fish indeed is included in the term "meat." Consequently, one who makes a Neder in that place not to eat meat is not allowed to eat fish. The Rambam adds that in all places one who makes a Neder not to eat meat is prohibited from eating fowl.
Why does the Rambam differentiate between fish and fowl? Why does he say that fish is considered "meat" in a place where a Shali'ach might bring back fish when asked to bring meat, but fowl is considered "meat" in all places and does not depend on what the Shali'ach might bring back?
ANSWER: The CHIDUSHEI CHASAM SOFER offers an ingenious explanation, based on the words of TOSFOS in Yevamos (71a, DH v'Hani). Tosfos writes that where it is clear how people use a particular word, we follow the popular usage as far as Nedarim are concerned, even if the Torah uses the word differently. On the other hand, when the popular usage of the word is not clear, for the purposes of Nedarim we follow the meaning of the word as it is used by the Torah.
The Chasam Sofer proves that it is clear that the Torah uses the word "Basar" to refer to the flesh of birds. The Torah says, "One may not eat a Neveilah and Tereifah and become Tamei" (Vayikra 22:8). RASHI there explains that this means that one who eats the Neveilah or Tereifah of a Kosher species of bird becomes Tamei when he swallows it ("Tum'as Beis ha'Beli'ah"). This proves that birds can be called "Tereifah." The Chasam Sofer states that whenever the prohibition of Tereifah applies, the prohibition of eating meat from a live animal also applies (see the Gemara on 102b, where Rebbi Yochanan states that the verse, "Do not eat meat that is torn (Tereifah) in the field" (Shemos 22:30), teaches the prohibition against eating flesh that was taken from a live animal, and the prohibition against eating the flesh of a Tereifah animal; see Insights there). Accordingly, the Torah's usage of the word "Basar" also includes birds, since the word "Basar" is used with reference to Tereifah.
(The Chasam Sofer points out that we cannot prove that "Basar" includes birds from the verses in Parshas Beha'aloscha, which describe how the Jewish people complained that they wanted "Basar" (Bamidbar 11:4), and Hash-m sent them quail (11:31). Perhaps the meat of birds is not considered "Basar," and the reason why Hash-m sent them quail was that there was no other meat available in the desert. It is similar to a Shali'ach who is told to bring "Basar," and he does not find any meat and thus returns to ask what he should bring.)
The Chasam Sofer writes that if the Torah would have said, "Do not cook Basar with milk," instead of, "Do not cook a kid with the milk of its mother" (Shemos 23:19, 34:26, Devarim 14:21), then all of the Tana'im would have agreed that it is forbidden mid'Oraisa to cook fowl with milk, and there would have been no dispute. However, since the Torah says, "Do not cook a kid with the milk of its mother," it is obviously excluding the meat of birds. The opinion that maintains that fowl cooked with milk is forbidden mid'Oraisa derives this from the rule that whatever can be forbidden as Neveilah is also forbidden to be cooked with milk (see TOSFOS to 113a, DH Basar).
In contrast, fish are never called "Basar" by the Torah. Even in the account of the Mabul, where the Torah says, "All Basar in the world died" (Bereishis 7:21), this does not refer to the fish, because the fish in the oceans survived (see Rashi to Bereishis 7:22).
Therefore, Rebbi Akiva maintains that since the Torah calls birds "Basar," and since in most places a Shali'ach would return to ask whether he should bring fowl when asked to bring "Basar," the Halachah is that in all places the term "Basar" includes fowl as well. In contrast, in a place where a Shali'ach would not return to ask about fish, the term "Basar" does not include fish, because "Basar" neither refers to fish in common speech, nor does the Torah use "Basar" to refer to fish. Only in a place where a Shali'ach would ask about fish when told to bring "Basar" is "Basar" considered to include fish. (D. BLOOM)
2) HALACHAH: THE PROHIBITION AGAINST EATING CHICKEN WITH MILK
OPINIONS: The Gemara discusses whether the prohibition to eat the meat of fowl with milk is mid'Oraisa or mid'Rabanan. What is the Halachah?
(a) TOSFOS (104b, DH Of) seems to conclude that eating fowl with milk is included in the Isur d'Oraisa of eating meat with milk.
(b) The RAMBAM (Hilchos Ma'achalos Asuros 9:4) rules that the Isur of eating fowl with milk is mid'Rabanan. (The Rabanan prohibited it as a safeguard against eating meat with milk.) This is also the view of the RIF as cited by the ROSH (8:51), the RASHBA, and others.
HALACHAH: The SHULCHAN ARUCH (YD 87:3) rules that the Isur to eat fowl with milk is mid'Rabanan. Moreover, the Rabanan prohibited only eating fowl with milk, but they did not prohibit cooking fowl with milk or benefiting from fowl cooked with milk (such as by selling it to a Nochri). Nevertheless, some Poskim prohibit cooking fowl with milk due to "Mar'is Ayin" when the meat of the fowl is not discernible from the meat of an animal, unless some indication is made to show that the meat is that of a fowl (for example, the feathers are left nearby). (See KAF HA'CHAYIM 87:25 and 36. See also PISCHEI TESHUVAH 87:8.)

104b----------------------------------------104b

3) WASHING THE HANDS AFTER EATING CHEESE
QUESTION: The Gemara relates that Rav Yitzchak, the son of Rav Mesharsheya, ate meat after cheese without washing his hands. They asked him that Agra rules that one does not need to wash his hands between eating cheese and fowl, which implies that one does need to wash his hands between eating cheese and the meat of an animal.
What is the Gemara's question? Agra is discussing one who eats "fowl and cheese," in that order: fowl first, and then cheese. Rav Yitzchak ate cheese first, and then meat. Although, as Agra implies, one must wash his hands after fowl before cheese, perhaps it is not necessary to wash when one eats meat after cheese. Indeed, a similar leniency appears in the Gemara later (105a), where the Gemara teaches that after one eats meat he must wait until the next meal before he eats cheese, while after one eats cheese he may eat meat immediately. (TOSFOS DH Of)
ANSWERS:
(a) TOSFOS answers that when Agra mentions one who eats "fowl and cheese," he certainly is not referring to one who eats fowl first and then cheese, because in his implied case of meat and cheese, it would not be sufficient to wash one's hands after eating meat before eating cheese, because one must wait until the following meal before he eats cheese. Rather, Agra must mean that there is no need to wash one's hands between fowl and cheese, whether one eats cheese first or fowl first. This implies that between eating meat and cheese, one must wash his hands; since Agra cannot be referring to eating meat first and then cheese, he must be referring to eating cheese first and then meat.
(b) According to RABEINU TAM and the BEHAG, one is permitted to eat cheese immediately after meat as long as he washes his hands and rinses his mouth. It is not necessary to wait until the following meal, unless he does not wash and rinse. According to this view, Agra still might be referring only to eating meat first and then cheese.
Tosfos suggests that according to Rabeinu Tam, it must be that the Gemara assumes that the order in which one eats meat and cheese does not make a difference with regard to washing one's hands between them. In both cases, one must wash his hands. The order makes a difference only with regard to rinsing one's mouth.
(c) The VILNA GA'ON (YD 89:1) suggests an original answer to the question of Tosfos. He explains that the Gemara had a tradition that Agra was referring only to a situation in which one eats cheese before eating fowl; in such a case one does not need to wash his hands. When one eats fowl first and then wants to eat cheese, he must wash his hands. Accordingly, with regard to eating cheese and the meat of an animal, one must wash his hands even when he eats cheese first and then wants to eat meat.

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