1) WHO SHALL RENDER HALACHIC DECISIONS
QUESTION: Rava derives from verses in the Torah that Halachic authorities will come only from the tribes of Levi and Yissachar. The Gemara explains that the other tribes certainly will produce scholars who will teach Halachah. However, only Levi and Yissachar will produce authorities with the ability to reach correct conclusions in Halachic matters ("Asukei Shemaita Aliba d'Hilchesa").
The MAHARSHA and others ask that the Gemara in Sanhedrin (93b) teaches that David ha'Melech was able to render correct Halachic decisions -- "Halachah Kemoso b'Chol Makom" -- even though he was not from Levi or Yissachar. Similarly, the Gemara in Eruvin (54a) says that David ha'Melech was "Gali Masechta" -- he merited to reach correct conclusions when he rendered Halachic rulings. What, then, does the Gemara here mean when it says that only scholars from the tribes of Levi and Yissachar can reach correct Halachic conclusions?
ANSWERS:
(a) The MAHARSHA answers that David ha'Melech was an exception because he was a king, and as a king he merited special Divine assistance.
(b) RAV YAKOV EMDEN says that scholars from Levi and Yissachar are "Asukei Shemaita Aliba d'Hilchesa" by themselves, without the need to confer with a Beis Din. David ha'Melech did not reach Halachic conclusions on his own. Rather, he consulted in all matters with his Rebbi, Mefiboshes, as the Gemara in Berachos (4a) says.
(c) The GEVURAS ARI explains that although David ha'Melech came from the tribe of Yehudah, he also descended from Levi through his matrilineal ancestry. RASHI (Shemos 1:21) mentions this when he says that David ha'Melech descended from Miriam (of the tribe of Levi), who merited to have the "House of Kingship" come from her in return for her selfless dedication in saving the lives of the Jewish babies born in Egypt.
(d) The Gevuras Ari suggests another answer. He says that the Gemara here means that among other tribes, only some of the Halachic authorities are able to reach correct conclusions on their own. However, most of the Halachic authorities from Levi and Yissachar are able to reach correct conclusions on their own, most of the time. David ha'Melech merited to be part of the minority of Halachic authorities from other tribes who were able to reach correct Halachic conclusions.

26b----------------------------------------26b

2) THE SEVENTEENTH KOHEN SELECTED BY THE "PAYIS"
QUESTION: A Beraisa taught by Rebbi Chiya states that the Payis sometimes selected 13 Kohanim to perform the various Avodos of the Korban Tamid, and sometimes it selected 14, 15, or 16. The Gemara questions this from another Beraisa which says that the Payis sometimes selected even 17 Kohanim. The Gemara answers that the Beraisa which says that the Payis sometimes selected 17 Kohanim does not follow the opinion of Rebbi Eliezer ben Yakov, who maintains that no Payis was done to select a Kohen to bring the Evarim from the Kevesh to the Mizbe'ach. This Tana maintains that an additional Kohen was selected by the Payis to bring the Evarim from the Kevesh to the Mizbe'ach.
The Gemara adds that the Tana of this Beraisa must follow the opinion of Rebbi Yehudah, who maintains that no separate Payis was done to select a Kohen for the Avodah of the Machtah (bringing the coals from the outer Mizbe'ach to the inner Mizbe'ach).
Why does the Gemara say that the Beraisa (which says that the Payis sometimes selected 17 Kohanim) must follow the opinion of Rebbi Yehudah? Perhaps the Payis selected a Kohen for the Avodah of the Machtah, and it does not select a Kohen to carry the Evarim to the Mizbe'ach. Accordingly, the Beraisa may follow the view of Rebbi Eliezer ben Yakov (and argue with Rebbi Yehudah).
ANSWERS:
(a) RASHI explains that the Beraisa counts all of the Kohanim who were selected by the Payis to perform an Avodah specifically related to the Korban Tamid. The Avodah of the Machtah was not an Avodah related to the Korban Tamid, but to the Ketores. (In this case, two separate Payesos were conducted to select the Kohanim for the Avodos related to the Korban Tamid. The first 16 Kohanim were selected with the first Payis, and the Kohen who would bring the Evarim from the Kevesh to the Mizbe'ach was selected by the fourth Payis.)
An Avodah that is unrelated to the Korban Tamid (such as the Machtah) is not included in the Beraisa's count of Kohanim. Thus, the Beraisa which says that 17 Kohanim were selected cannot follow the view of Rebbi Eliezer ben Yakov, because he says that no Payis was done to select a Kohen to bring the Evarim to the Mizbe'ach.
The Rishonim reject this explanation. Whether or not the Beraisa follows Rebbi Yehudah is irrelevant. Even if the Beraisa disagrees with Rebbi Yehudah and maintains that an extra Kohen was selected by the Payis to bring the Machtah, that Avodah cannot be included in the count because it is not related to the Korban Tamid.
(Rashi answers this point when he says that the Gemara mentions that the Beraisa follows Rebbi Yehudah only incidentally. That is, it so happens that Rebbi Yehudah is the Tana who argues with Rebbi Eliezer ben Yakov, as the Gemara says earlier on this Daf.)
(b) The other Rishonim write that the proper Girsa of the Gemara is the original Girsa (before Rashi's emendation), according to which the Gemara says that the Beraisa is in agreement with neither Rebbi Eliezer ben Yakov nor Rebbi Yehudah. The Gemara explains that it cannot follow Rebbi Yehudah, because he maintains that only 16 Kohanim were selected, and not 17. TOSFOS (DH ha'Hi) explains that the Beraisa which mentions 17 does not refer to the Kohanim chosen only for the Avodos of the Tamid. Rather, it refers to the Kohanim chosen by all of the Payesos for all of the Avodos. Moreover, it refers to an ordinary week day, and not to a special day (such as Yom Tov of Sukos which occurs on Shabbos). The number of Kohanim selected on a normal day to perform all of the Avodos was 17. Thirteen Kohanim performed the Avodos of the Tamid, and four others performed the Avodos of the Terumas ha'Deshen, Ma'aleh Evarim l'Mizbe'ach, the Ketores, and the Machtah.
According to Rebbi Yehudah, however, the Avodah of the Machtah cannot be included in the count, because Rebbi Yehudah says (25b) that there was no Payis for the Machtah (but rather the Kohen who won the Payis of the Ketores would tell the Kohen next to him to take the Machtah).
However, what difference does it make if the Machtah was not chosen directly by a Payis but indirectly through the Payis of the Ketores? The Avodah of the Machtah still should be counted, just as the Kohanim who performed the Dishun, Hatavah, and who brought the Evarim of the Tamid to the Kevesh are included in the count even though they were selected only indirectly through one actual Payis (the Kohanim who were standing next to the single Kohen whom the Payis selected would be selected for these Avodos).
Tosfos answers that the selection-process for the Avodah of the Machtah did not work the same way as it did for the Avodos of the Dishun, Hatavah, and bringing the Evarim to the Kevesh. The Kohen who stood next to the winner of the Payis of the Ketores was not automatically chosen to bring the Machtah. Rather, the winner of the Ketores was entitled to choose to take the Machtah himself or to appoint any Kohen of his choice to take the Machtah. Consequently, according to Rebbi Yehudah there was no Payis at all for the Machtah. Rebbi Yehudah cannot be the Tana of the Beraisa, because the only way to have a total of 17 Kohanim selected by the Payis is to include the Kohen who brings the Machtah.
(c) RABEINU CHANANEL concurs that the Girsa of the Gemara is that the Beraisa is not in agreement with Rebbi Yehudah. According to Rebbi Yehudah, the maximum number of Kohanim selected by the Payis was 16, and not 17. Rabeinu Chananel explains that the Beraisa counts only the Kohanim selected by the second Payis, regardless of whether or not the specific Avodah is related to the Korban Tamid. According to Rebbi Yehudah, though, the Machtah was chosen (indirectly) during the third Payis, and therefore the number of Kohanim chosen by the second Payis totaled at most 16 (on Yom Tov of Sukos which occurs on Shabbos). The Tana of the Beraisa maintains that the selection of the Kohen for the Avodah of the Machtah was the seventeenth selection, carried out during the second Payis. Since this Tana includes the Machtah in the second Payis instead of in the third (in which a Kohen was chosen to offer the Ketores), it is clear that he argues with Rebbi Yehudah.
Why, though, does this Tana maintain that the Kohen who would perform the Avodah of the Machtah was not chosen together with the one who would offer Ketores on the coals that were brought by the Machtah? Logically, the two should be chosen together. Rabeinu Chananel answers that this Tana maintains that the Avodah of the Machtah did not make the Kohen who performed it wealthy, and thus there was no reason to limit the Payis for the Machtah to Kohanim who had never done it before. (See Insights to Yoma 25:2.) Therefore, it was included in the second Payis in which all Kohanim participated, and not in the third which was limited to "new" Kohanim.
The Tana of the Beraisa is also not in agreement with Rebbi Eliezer ben Yakov. Since Rebbi Eliezer maintains that no Payis was done for the bringing of the Evarim to the Mizbe'ach, the fourth Payis must have been done for the Machtah (as the Gemara says at the beginning of this Daf). Consequently, the Machtah was still not included in the second Payis, which is the only one that the Beraisa here discusses.
In summary, according to Rabeinu Chananel there are three opinions as to when the Kohen was chosen to carry the Machtah: Rebbi Yehudah maintains that he was chosen during the third Payis, along with the Kohen who offered the Ketores. Rebbi Eliezer ben Yakov maintains that a fourth Payis was done to choose the Kohen to bring the Machtah. The Tana of the Beraisa maintains that the Machtah was selected during the second Payis.

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