(a)If Tum'ah was discovered inside the Heichal, were Leviyim and Yisraelim permitted in to remove it?
(b)Who was not permitted to enter even for the purpose of removing Tum'ah?
(a)If there were no Kohanim available, to remove Tum'ah from the Heichal, then they would send in Leviyim to remove it, and if there were no Leviyim, they would send in Yisraelim.
(b)But that is only on the condition that they were Tahor, but not if they were Tamei.
(a)How did Rav Kahana explain the Pasuk in Acharei Mos "Ach el ha'Poroches Lo Yavo"?
(b)What title did that earn him?
(c)They asked a She'eilah whether, if there was a choice, should they allow a Kohen who is Tamei to go into the Mikdash (if necessary), or a Kohen with a blemish. What are the two sides of the She'eilah?
(a)From "Ach el ha'Poroches Lo Yavo (ve'El ha'Mizbe'ach Lo Yigash)" - Rav Kahana learns that, even though a blemished Kohen is forbidden to enter inside the area between the Ulam and the Mizbe'ach for the Avodah etc., he is nevertheless permitted to enter even within the Paroches (of the Kodesh Kodshim), to make new gold plates to cover the walls. Initially, it should be un-blemished Kohanim who are sent in; but if there are none, then even blemished Kohanim may go in to perform the task on hand; and if no Tahor Kohanim are available, then one may even send in Tamei Kohanim (but not Yisraelim). Note: This appears to clash with the opinion quoted in 1.
(b)This earned him the title of 'Rav Kahana Mesayei'a Kohanim'.
(c)Rav Chiya bar Ashi Amar Rav holds that a Tamei Kohen takes precedence over a blemished one, since he is permitted to serve by Avodas ha'Tzibur (because 'Tum'ah Hutrah b'Tzibur' - which a blemished Kohen is not); whereas Rebbi Elazar gives precedence to a blemished Kohen, who is permitted to eat Kodshim (which a Tamei Kohen is not); and those are the two sides of the She'eilah. Note: Rav Kahana's Beraisa concurs with Rebbi Elazar.
(a)'Rebbi Shimon Omer, Makom she'Hitiru Lecha Chachamim, Mishelecha Nasnu Lecha; she'Lo Hitiru Lecha Ela Mishum Shevus'. Rebbi Shimon is explaining why he was lenient in another area of Eruv. Which area, and what was his reason for being lenient there?
(b)But he is strict with regard to tying the string of a harp which broke (above 102b). What does he hold there, and what is his reason for that?
(a)'Rebbi Shimon Omer, Makom she'Hitiru Lecha Chachamim, Mishelecha Nasnu Lecha; she'Lo Hitiru Lecha Ela Mishum Shevus' - refers to the Sugya above 52b, where the Tana Kama forbade someone who is even one Amah outside the Techum of the town when Shabbos enters, to enter. Rebbi Shimon there permitted him to enter because of To'ei ha'Midos (as we explained there). Here he gives the reason for what he says there - namely, because Chazal are only giving him what they took away from him in the first place (the fifteen Amos 'error' that were made).
(b)He is strict with regard to tying the string of a harp which broke (above 102b) - The Tana Kama there permitted tying a broken harp-string even using a regular knot, to which Rebbi Shimon replied that they only permitted tying a bow, which cannot come to an Isur d'Oraysa, but as far as tying a knot is concerned, since this can lead to an Isur d'Oraysa outside the Beis Hamikdash, they did not permit it in the Mikdash, even a casual knot.
HADRAN ALACH, HA'MOTZE TEFILIN, U'SELIKA LAH MASECHES ERUVIN