1) HOW MANY "CHALOS" IS THE KOHEN GADOL ENTITLED TO TAKE
QUESTION: The Beraisa states that the Kohen Gadol is entitled to "four or five" of the twelve Chalos of the Lechem ha'Panim. Abaye explains that the Tana of the Beraisa follows the opinion of the Rabanan who maintain that the Kohen Gadol is entitled to less than half of the total of the products distributed to the Kohanim in the Beis ha'Mikdash. Since the twelve Chalos of Lechem ha'Panim are normally divided among the two Mishmaros (the incoming one and the outgoing one), the Kohen Gadol is entitled to five Chalos, since that is just less than half of the total number of Chalos. Why, though, does the Beraisa mention that he may take "four or five" Chalos?
Abaye explains that the Beraisa's statement that the Kohen Gadol may take four Chalos follows the opinion of Rebbi Yehudah. Rebbi Yehudah maintains that when the incoming and outgoing Mishmaros divide the Chalos, the new Mishmar receives seven and the old Mishmar receives five. Two Chalos are always reserved for the new Mishmar as a reward for closing the doors of the Azarah which were opened by the outgoing Mishmar. Since the two Mishmaros, according to Rebbi Yehudah, divide only ten of the Chalos, the Kohen Gadol takes just less than half, which is four. He does not share the Chalos that are given as a reward; he shares only those Chalos which are given as part of the Avodah in the Beis ha'Mikdash.
The GEVURAS ARI asks that the Gemara assumes that according to Rebbi Yehudah, the outgoing Mishmar must give two Chalos to the incoming Mishmar, which leaves only ten Chalos from which the Kohen takes just less than half (i.e. four). However, the reason why the new Mishmar receives seven Chalos and the old Mishmar receives five is not because the old Mishmar gives two to the new Mishmar as a reward. Rather, each Mishmar originally was entitled to six Chalos, and the old Mishmar gives only one Chalah to the new Mishmar. In that way, the old Mishmar receives five and the new Mishmar receives seven. Consequently, the Kohen Gadol should be entitled to half of all of the Chalos which are not used as a reward. Since only one is used as a reward, that leaves eleven from which the Kohen Gadol is entitled to take just less than half. Accordingly, even Rebbi Yehudah should agree that he receives five Chalos, and not four!
ANSWERS:
(a) The GEVURAS ARI answers that it is true that eleven Chalos, and not ten, are divided among the two Mishmaros, and, in theory, the Kohen Gadol should receive five Chalos even according to Rebbi Yehudah. However, if he were to receive five Chalos, it would not be evident that he is entitled to just less than half. One might mistakenly think that perhaps the Kohen Gadol is entitled to receive exactly half, and that is why he receives five Chalos. Although half of eleven is five and a half, it is not respectful to give the Kohen Gadol an incomplete loaf, and therefore he receives five, but normally he receives exactly half of the total amount that is distributed to the Kohanim. In order to show that the Kohen Gadol is entitled only to less than half, but not to exactly half, he is given only four Chalos according to Rebbi Yehudah.
(b) The Gevuras Ari assumes that the extra Chalah which the incoming Mishmar receives is granted to them by the outgoing Mishmar from their own portion (as a reward for closing the doors for them). Accordingly, all twelve Chalos are divided, and that is why the outgoing Mishmar receives five and the incoming Mishmar receives seven (the outgoing Mishmar gives one of "their" Chalos to the incoming Mishmar). However, if all twelve Chalos are divided, the Kohen Gadol still receives five Chalos (one less than half). Once he is given five Chalos, seven Chalos are left to be divided among the two Mishmaros. Each Mishmar should receive three and a half Chalos, and the outgoing Mishmar should give one of those to the incoming Mishmar as its reward. (The reward should not be lessened by the amount that the Kohen Gadol took.)
It seems that it is not the outgoing Mishmar which gives of its own portion to the incoming Mishmar. Rather, it is a "Tenai Beis Din" -- a stipulation that Beis Din established in the distribution of the Chalos -- that the incoming Mishmar receives two extra Chalos. Accordingly, those Chalos are given to the incoming Mishmar before all of the Chalos are divided, and thus only ten remain to be divided. The Kohen Gadol is entitled to less than half of those, which is four. (M. Kornfeld)
2) WHY THE KOHEN GADOL RECEIVES LESS BECAUSE OF THE "MISHMAR HA'MIS'AKEV"
QUESTION: The Beraisa states that the Kohen Gadol is entitled to "four or five" of the twelve Chalos of the Lechem ha'Panim. Rava explains that the Tana of the Beraisa follows the opinion of Rebbi, who maintains that the Kohen Gadol is entitled to half of the total of the products distributed to the Kohanim in the Beis ha'Mikdash. The Tana of the Beraisa also follows the view of Rebbi Yehudah, who says that two Chalos are given to the incoming Mishmar as a reward for closing the doors of the Azarah. Consequently, the Kohen Gadol receives half of the ten Chalos that remain, or five Chalos.
When the Beraisa says that the Kohen Gadol receives "four or five" Chalos, it refers to a case of a "Mishmar ha'Mis'akev." In such a case, the Mishmar ha'Mis'akev receives two Chalos, and thus only eight are left for distribution, of which the Kohen Gadol receives half, or four Chalos.
The Mishmar ha'Mis'akev is a Mishmar (or group of Mishmaros) who either remained in the Beis ha'Mikdash for an extra day at the beginning of the week, after their term of service was over (for example, when Yom Tov concluded on Thursday, they remained until Sunday), or who came a day early to the Beis ha'Mikdash at the end of the week (for example, they arrived on Friday when Yom Tov began on the following Monday) and had to remain there over Shabbos. That Mishmar is not included in the normal division of the Chalos of Lechem ha'Panim, which are divided among the Mishmaros that are present in the Beis ha'Mikdash on Shabbos (the incoming and outgoing Mishmaros). Rather, they receive only two Chalos. The rest are divided among the two Mishmaros on duty.
The GEVURAS ARI and MAHARSHAM ask that the Mishmar ha'Mis'akev, the Mishmar that stays behind, is not required to be there. On the contrary, they are not supposed to be there, as Rashi implies. Why, then, should the Kohen Gadol receive less than he would normally receive as a result of that Mishmar? Instead of diminishing the Kohen Gadol's share, we should diminish that Mishmar's share. Why does the Kohen Gadol receive less because of them?
ANSWER: The GEVURAS ARI answers that the Rabanan enacted that the Mishmar that stays behind receives two Chalos. It is not because they deserve it; rather, it is purely due to the generosity of the Rabanan who made the enactment for their benefit. They receive the Chalos by virtue of a Takanah, and not because of an apportionment (Chalukah), while the other two Mishmaros and the Kohen Gadol receive their share through an apportionment. Just as the Rabanan have the authority to diminish the amount of Chalos which the other two Mishmaros receive (as a result of their Takanah), they also have the authority to diminish the amount of Chalos which the Kohen Gadol receives.

18b----------------------------------------18b

3) MARRIED TO TWO WIVES IN TWO PLACES
QUESTION: The Gemara relates that when Rav and Rav Nachman (and presumably other Amora'im) traveled to distant towns, they would marry other wives in those towns as a way of preventing any nocturnal mishaps from occurring.
The Gemara asks that marrying a wife in the new town will not help to prevent a nocturnal mishap, because a newly married man and woman are not be permitted to be with each other for at least seven days; the excitement of the marriage causes the woman to have a flow of "Dam Chimud" and become a Nidah right away. The Gemara answers that the Amora'im either informed the women whom they intended to marry seven days earlier, or that they did not actually consummate the marriage with them, but merely performed Yichud with them, and thus the psychological effect of having "Pas b'Salo" ("bread available in his basket") prevented nocturnal mishaps.
According to the Gemara's second answer, how can the woman be considered "Pas b'Salo" if she is forbidden to him because of "Dam Chimud"? (TOSFOS DH Yechudi)
ANSWERS:
(a) TOSFOS (in his explanation of Rashi) and the RAMBAM (Hilchos Isurei Bi'ah 11:10) write that the Gemara means "Pas b'Salo l'Achar Zeman," she will become permitted to him after seven days. This is called "Pas b'Salo" because he knows that she will be permitted to him in a matter of days. (That is, she is "available" to him as far as the prohibition of being alone with an unmarried woman is concerned, even though she is not available to him as far as the prohibition of Nidah is concerned. Since a Nidah normally becomes permitted in a matter of days, she is called "Pas b'Salo.")
(b) TOSFOS and other Rishonim explain that the Amora'im were only "Tove'a l'Yichud" -- they asked the women to marry them only in order to perform Yichud with them after marriage, but not to have marital relations. Since the women were informed that the purpose of the marriage was only for Yichud, they had no expectations of intimacy, and thus they did not have a flow of "Dam Chimud." (Moreover, if the Amora'im later decided to consummate the marriage, there would be no "Dam Chimud" at that time because the women were already married to them. "Dam Chimud" occurs only when a marriage proposal is offered to a woman who is not married.)
This explanation also answers the previous question of the Gemara. The Gemara asked that one is not permitted to have two wives in two different places lest it lead to problems of Mamzerus. Since the Amora did only Yichud with the second woman, there was no concern that problems of Mamzerus would arise. If he later would decide to consummate the marriage, he would bring her to his hometown.
(c) The RI HA'LAVAN and RA'AVAD (Hilchos Isurei Bi'ah 11:10) explain that the word "Yichud" here does not mean "isolate" themselves. Rather, it means "set aside" for themselves. The Amora did not ask a woman to marry him, but to "set herself aside" for marriage and to make herself available in case he would decide to marry her. This was considered "Pas b'Salo" since the woman was ready to marry him at any moment.
There is no problem of "Dam Chimud" in such a situation for reasons similar to those suggested by Tosfos. A man's request that a woman "be ready" for marriage is not a formal marriage proposal, and thus there is no "Dam Chimud." When he later proposes to her and marries her, she will not have "Dam Chimud" because the proposal was expected and did not take her by surprise. (This approach also answers the earlier question of the Gemara, as described in (b) above.)

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