1) THE TWO "CHIDUSHIM" OF REBBI MEIR
QUESTION: Rebbi Elazar quotes Bar Kapara who taught two Halachos in the name of Rebbi Meir. First, he taught that Evarei Olah (the limbs of a Korban Olah) that were left over from the burning of the Olah must be burned on a separate Ma'arachah. Second, he taught that Evarei Olah that were left over from a weekday Korban may be burned on Shabbos.
The Gemara inquires what new Halachah Bar Kapara intends to teach. Both Halachos that he mentions are written explicitly in a Beraisa (45a) in which Rebbi Meir states that there is a separate Ma'arachah for the Evarim that are left over (the first Halachah quoted by Rebbi Elazar). In the same Beraisa, Rebbi Meir states that on Yom Kippur (a day comparable to Shabbos), the Ma'arachah for the leftover Evarim may be used (the second Halachah quoted by Rebbi Elazar). The Gemara answers that each statement is necessary for various reasons.
RASHI's comments here are difficult to understand. Rashi (DH Hachi Garsinan) writes that the text that apparently was printed in some editions of the Gemara is incorrect. What was the variant text of the Gemara, and why does Rashi change it? (A word seems to have been omitted from the end of Rashi's comments. Before the words "d'Hadar Parich," the word "Leisa" should be added so that Rashi's comment reads, "Leisa, d'Hadar Parich" -- "that is incorrect, because the Gemara then asks....")
ANSWER: The BACH explains that in Rashi's edition of the Gemara, Rebbi Elazar says that the Evarim of an Olas Shabbos that are left over are burned on a separate Ma'arachah.
However, if this was the variant text that Rashi rejects, then Rashi should have rejected this text for a more basic reason. It is clear from the continuation of Rebbi Elazar's statement in which he says "and even on Shabbos" that the first part of his statement does not refer to Shabbos.
The SI'ACH YITZCHAK explains the words of Rashi based on the explanation of TOSFOS in Menachos (40b, DH Techeles). In the text of Rashi's edition of the Gemara, the first part of Rebbi Elazar's statement, in which he says that a separate Ma'arachah is made for leftover Evarim even on Shabbos, includes the words "the Evarim of an Olas Chol." According to that text, however, the first and second parts of Rebbi Elazar's statement comprise only one Halachah -- that the leftover Evarim of a weekday Korban may be burned even on Shabbos. His statement does not teach that there is a fourth Ma'arachah. What, then, is the Gemara's question when it asks, "What is he teaching us? We already learned that there is a separate Ma'arachah according to Rebbi Meir." According to this Girsa, Rebbi Meir (as quoted by Rebbi Elazar) is not teaching that there is a separate Ma'arachah!
Therefore, Rashi says that the proper Girsa is "the Evarim of an Olah" (and not "the Evarim of an Olas Chol") have their own Ma'arachah, and even on Shabbos. Accordingly, the first part of Rebbi Elazar's statement is separate from the second part, and it teaches that a separate Ma'arachah is made. The second part of his statement teaches that the separate Ma'arachah is made even on Shabbos. According to this Girsa, the continuation of the Gemara (in which it asks why each Halachah is necessary) is clear.
TOSFOS in Menachos (40b) and TOSFOS YESHANIM here defend the original Girsa of "Olas Chol," even though according to that Girsa Rebbi Meir is not teaching that there is an additional Ma'arachah. Tosfos says that the letter "Vav" added to the word "v'Afilu" makes it evident that Rebbi Meir's statement includes two Halachos. The words "v'Afilu b'Shabbos" imply that he is adding to a previously stated Halachah.

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