1) FEEDING FORBIDDEN FOOD TO A SICK PERSON
OPINIONS: The Mishnah states that one is permitted to feed any type of food, even forbidden food, to one who is afflicted with "Bulmus," a dangerous illness which results from hunger (Rashi). The Gemara cites a Beraisa which says that when there is no permitted food available, and the only foods available are a food prohibited by a very severe Isur and a food prohibited by a less severe Isur, one should feed to the sick person the less severe Isur. For example, if the only foods available are a fruit of Tevel and meat of Neveilah, one should feed the Neveilah to the sick person. Neveilah is forbidden only by a Lav and is punishable with Malkus, while Tevel is punishable with Misah b'Yedei Shamayim. This Halachah applies to any sick person in mortal danger.
A logical corollary to this rule should be that if the choice would be to feed a sick person Neveilah or to desecrate Shabbos (in order to slaughter an animal properly), one should choose the Neveilah because the desecration of Shabbos is punishable with Sekilah, a more severe punishment than Malkus. However, the Rishonim rule otherwise. They rule that one should desecrate Shabbos and not feed him Neveilah. (This is also implied by the Gemara in Chulin (14b) which permits one to slaughter an animal for a sick person on Shabbos and does not specifically limit that allowance to a case in which there is no Nochri available to kill the animal.) Why is Shabbos different?
(a) The RA'AVAD (cited by the ROSH and the RAN) explains that the allowance to feed an Isur to a sick person applies only to the specific Isur which prevents him from eating. On Shabbos, when a person needs to eat because of Piku'ach Nefesh, it is not the fact that a Neveilah is prohibited that prevents him from eating. Rather, it is the Isur against slaughtering an animal on Shabbos that prevents him from eating (because, if not for Shabbos, he would simply slaughter an animal and eat it). Therefore, it is the Isur against slaughtering on Shabbos which may be pushed aside for the sake of the sick person.
The RAN, however, takes issue with the Ra'avad's ruling. If the meat of Neveilah is available on Shabbos, then both the Isur of Neveilah and the Isur against slaughtering on Shabbos stand in his way of eating. Why should the Isur of Neveilah not be pushed aside? After all, it is less severe than the Isur of Melachah on Shabbos.
Perhaps the Ra'avad means that an Isur which applies only at certain times (or in some other limited way) is always pushed aside before an Isur that applies constantly. The limited Isur is viewed as the Isur which presently stands in his way, since, under other circumstances, it would not apply. Therefore, the Isur against slaughtering on Shabbos must be pushed aside before the Isur of Neveilah. (M. KORNFELD)
(b) The ROSH, in an entirely different approach, says that the sick person might be so disgusted by the Neveilah that he will not be able to eat it and his life will be in more danger. Therefore, it is better to slaughter an animal for him.
(c) The RAN explains that in this case, the Isur of Neveilah is more severe than the Isur against slaughtering on Shabbos. When the sick person eats Neveilah, each k'Zayis of meat that he eats constitutes an additional Lav. A person who performs Shechitah on Shabbos transgresses the Isur only once. Therefore, it is preferable to slaughter an animal on Shabbos for the sick person than to feed him Neveilah.

83b----------------------------------------83b

2) THE REASON FOR THE PROHIBITION AGAINST SEPARATING TERUMOS AND MA'ASEROS ON SHABBOS
QUESTION: The Gemara says that the act of separating Terumos and Ma'aseros on Shabbos is prohibited mid'Rabanan because it involves "Tiltul Muktzah," handling Muktzah (produce of Tevel is Muktzah).
However, the Gemara in Beitzah (37a) implies that the prohibition is due to a Gezeirah to prevent one from conducting business transactions ("Mekach u'Memkar") on Shabbos. When one sanctifies an item, he transfers its ownership to Hekdesh. Similarly, when one separates Terumos and Ma'aseros, he transfers its ownership. Moreover, RASHI in Beitzah (9a, DH Ochel v'Holech) adds that the act of separating Terumos makes the produce edible, and thus it is prohibited because it appears as though one is fixing an item ("Metaken").
Why does the Gemara here say that it is prohibited because of Tiltul Muktzah? (REBBI AKIVA EIGER in GILYON HA'SHAS. Rebbi Akiva Eiger cites the Gemara in Yevamos (93a) which also prohibits separating Terumah and Ma'aser because of Tiltul.)
ANSWER: The TOSFOS YOM HA'KIPURIM explains that the act of separating Terumos and Ma'aseros is prohibited for more than one reason. The Isur of Metaken prohibits separating Terumos and Ma'aseros in a case in which one does not need to touch or handle the Tevel (such as when the fruit is already separated into two piles, and one merely needs to designate one of the piles as Terumah). In such a case, Tiltul Muktzah does not apply, and the act is prohibited because of Metaken.
Why, though, does the Gemara here mention the less common problem of Tiltul, when the reason of Metaken applies in every case?
The Gemara's intention is to emphasize that although the Isur d'Rabanan of Tiltul is as powerful as an Isur d'Oraisa, as the TOSFOS YESHANIM writes in Beitzah (3b), nevertheless it certainly is preferable to transgress the Isur of Tiltul and not to transgress an Isur d'Oraisa. It is obvious that the Isurim of Metaken and Mekach u'Memkar are pushed aside in order not to transgress an Isur d'Oraisa. The Gemara here teaches that even though Tiltul is forbidden mi'Divrei Kabalah (Shabbos 123b) and is comparable to an Isur d'Oraisa, it is pushed aside to prevent the transgression of an actual Isur d'Oraisa. (The same logic applies to the Gemara in Yevamos which Rebbi Akiva Eiger quotes, which attempts to prove that the Isur to separate Terumah is mid'Rabanan and has no source in the Torah.) (M. KORNFELD)
3) AGADAH: THE MAD DOG AND LASHON HA'RA
The Gemara quotes a Beraisa which lists five characteristics with which a person can identify a mad dog: its mouth hangs open, spittle trickles down from its open mouth, its ears hang low, its tail rests between its legs, and it walks along the far side of the road. Some add that it barks but its voice is not heard.
Shmuel says that the danger of a mad dog is the Ru'ach Ra'ah that rests upon it. To support Shmuel, the Gemara cites a Beraisa which states that one who attempts to kill a mad dog must do so only from afar (such as by throwing something at it), so that he not be harmed by the Ru'ach Ra'ah. The Beraisa continues and says that one who rubs against a mad dog is in danger, and the only remedy is to throw off his clothes immediately and run away. The Beraisa adds that a person who is bitten by a mad dog surely will die (Abaye, however, describes an antidote to the bite of a mad dog).
The CHAFETZ CHAIM (in SHEMIRAS HA'LASHON, Sha'ar ha'Zechirah, ch. 4) cites the Midrash (Yalkut Shimoni, Parshas Ki Setzei) which compares a person who speaks Lashon ha'Ra to one who is bitten by a mad dog. The Chafetz Chaim points out that just as there is no remedy for the bite of a mad dog, there is no atonement for one accustoms himself to speaking Lashon ha'Ra. The Gemara in Erchin (16b) says that one who habitually speaks Lashon ha'Ra has no atonement.
Why does the Midrash specifically compare a person who speaks Lashon ha'Ra to one who was bitten by a mad dog?
The Chafetz Chaim, based on the Gemara here, describes how a person who speaks Lashon ha'Ra has all of the attributes of a mad dog. The Ru'ach Ra'ah that rests on a mad dog causes it to have the characteristics enumerated by the Beraisa. When the dog bites, the Ru'ach Ra'ah is transmitted to the person who then develops all of the attributes of the mad dog. One who speaks Lashon ha'Ra also has these attributes, as though a Ru'ach Ra'ah rests upon him. The Chafetz Chaim elaborates:
1. A mad dog's mouth hangs open. Similarly, the mouth of the person who speaks Lashon ha'Ra is always open, waiting to find any listener with whom to share his gossip.
2. Its spittle trickles down. The mad dog is always ready to attack anyone it meets, as indicated by its constant flow of spittle. Similarly, the person who speaks Lashon ha'Ra is always eager to speak about anyone whose name comes up in conversation. In addition, the spittle of a dog is most disgusting, especially that of a mad dog. The dog leaves a path of saliva behind wherever it goes. Similarly, the disgusting speech of the person who speaks Lashon ha'Ra leaves its impact wherever he goes.
3. Its ears hang low. By hanging its ears, the mad dog makes itself look uninterested in attacking anyone, so that no one will be afraid to come near it. This tactic enables the dog to easily pounce on its prey.
4. Its tail rests between its legs. For the same reason that it keeps its ears low, the mad dog walks slowly and does not run excitedly. It gives the impression that it is harmless.
5. It walks along the far side of the road. The dog walks apart from the central flow of people and gives the impression that it is uninterested in attacking anyone.
Some add that it barks but its voice is not heard. This is another guise that it engages to give the appearance of a quiet, happy, kind-hearted canine, so that whoever sees it will assume that it is harmless and will take no measure of caution. It then is poised to viciously attack its unsuspecting victim.
The person who speaks Lashon ha'Ra demonstrates these attributes as well. He walks humbly, away from other people, so that they will think he is not interested in their affairs and that he does not spread gossip. When he speaks Lashon ha'Ra, he does it in such a sly way that at first it is not evident that he is speaking Lashon ha'Ra. His ears are down as though he is not listening to anyone else's private conversations, and he walks along as though he is minding his own business, so that others will be unprepared when he comes to attack with his vicious Lashon ha'Ra. Just as a mad dog barks and no voice is heard, the one who speaks Lashon ha'Ra does damage that is not noticeable right away.
Finally, just as one who rubs against a mad dog must throw off his clothes and run away quickly, one who comes near a person who is known to speak Lashon ha'Ra should run away immediately, even at the cost of significant embarrassment.

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