1) AN ACT OF "MIS'ASEK" OF "ME'ILAH"
QUESTIONS: The Gemara explains the Beraisa cited earlier (32b) which says that Me'ilah is more severe than other sins in one respect. The Gemara offers several ways to explain why Me'ilah is more severe than all other sins. Mar brei d'Ravna suggests that one is liable for Me'ilah even when he does the act without intent ("Eino Miskaven"), while one is not liable for any other sin that he does without intent. For example, on Shabbos, if one intends to cut an item which he is permitted to cut (it is already detached from the ground) and he unintentionally cuts an item which he is forbidden to cut (it is attached to the ground), he is exempt, because he did not do what he intended to do. In contrast, one is liable for Me'ilah when he intends to warm himself with fabric of Chulin and he unintentionally warms himself with the wool of a Korban Olah.
RASHI (DH she'Im Niskaven) explains that the words "Eino Miskaven" in the context of this Gemara refer to what is usually known as "Mis'asek," one who performs a sin without intention to do so. Rashi writes that one who is Mis'asek is exempt not only in the case of other Mitzvos, but "even on Shabbos," because in order to be liable one must do a "Meleches Machsheves," a Melachah done intentionally.
Rashi's words are difficult to understand.
What does Rashi mean when he says that "even" on Shabbos one is exempt for Mis'asek? Why would we have thought that desecration of Shabbos is more stringent than other sins, such that Rashi needs to emphasize that "even" on Shabbos one is exempt?
Moreover, Rashi writes that Mis'asek is exempt on Shabbos because one is liable only for "Meleches Machsheves," an act done intentionally. The words "Meleches Machsheves" refer specifically to Shabbos, and they teach that with regard to Shabbos one must have intention to perform the Melachah in order to be liable. Why, then, does Rashi imply that it is more obvious that Mis'asek is exempt for other sins than for Shabbos? The principle of "Meleches Machsheves" should make it more obvious that Mis'asek is exempt for Shabbos than for other sins.
In addition, TOSFOS RABEINU PERETZ, TOSFOS HA'ROSH, and TOSFOS SHANTZ, as well as the PNEI YEHOSHUA point out that not only does the exemption of "Meleches Machsheves" not apply to other sins, but the Gemara elsewhere clearly says that one is liable for Mis'asek for other sins (Shabbos 73a, and Rashi there, DH d'Savur). Why, then, does Rashi say that one is exempt for Mis'asek "even on Shabbos," when the exemption of Mis'asek applies only on Shabbos?
ANSWER: The DEVAR SHMUEL suggests that Rashi here maintains that the exemption of Mis'asek does apply to sins other than Shabbos. (This is derived from the word "Bah" in Vayikra 4:23; see Kerisus 19b and Insights to Kerisus 19:2.) Even though one is also exempt for Mis'asek on Shabbos as well, that exemption is not due to the normal exemption of Mis'asek. Rather, an entirely different source teaches the exemption of Mis'asek on Shabbos -- the source that teaches that Shabbos requires "Meleches Machsheves" (see Rashi to Chagigah 10b, DH Meleches).
Why is this additional verse necessary? This verse is necessary because the general exemption of Mis'asek does not suffice to exempt one for an unintentional desecration of Shabbos, for the following reason. The law is that a person who performs a Melachah on Shabbos thinking that it is a weekday is obligated to bring a Korban Chatas. Why is his act of unintentional transgression not included in the general exemption of Mis'asek?
The CHELKAS YO'AV (OC 7) concludes that there is a Gezeiras ha'Kasuv that teaches that the exemption of Mis'asek does not apply to this type of desecration of Shabbos. Consequently, we might have thought that one is liable for all other forms of Mis'asek on Shabbos as well based on the same Gezeiras ha'Kasuv. Rashi here teaches that "even on Shabbos" one is exempt for the other forms of Mis'asek because of the verse of "Meleches Machsheves." That is, he is exempt when he knew that it was Shabbos but he intended to do an act that was permitted and unintentionally did an act that was forbidden. "Even" with regard to Shabbos, Mis'asek exempts him in such a case.
2) SEPARATING TERUMAH FROM CHAMETZ ON PESACH
QUESTION: The Gemara (32a) records a dispute among the Tana'im with regard to whether one is liable for transgressing the prohibition against eating Chametz when he eats Chametz of Terumah on Pesach. The Gemara adds that the dispute applies only when the Chametz was made into Terumah prior to Pesach. If the grain became Chametz on Pesach before Terumah was separated from it, everyone agrees that the Chametz is not Terumah and one is liable for eating Chametz on Pesach.
Rav Huna brei d'Rav Yehoshua explains that one is liable because the Torah calls Terumah "Reishis" (Devarim 18:4), which is understood to mean "Reishis she'Sheyareha Nikarin," a "first portion that leaves behind a recognizable remainder." This means that one of the conditions of Terumah is that it must permit the rest of the produce from which it was separated. If one may not eat the remainder of the produce even after Terumah is separated from it, then his act of separating Terumah is ineffective. In the case of Chametz (that is Tevel) on Pesach, the Chametz remains forbidden even after Terumah is separated from it, because of the Isur of Chametz.
REBBI AKIVA EIGER (in Gilyon ha'Shas) and the TZELACH ask that according to the Gemara, since the validity of Terumah depends solely on the remainder of the produce, Terumah cannot be separated from Chametz on Pesach because the act does not serve to permit the remaining grain. It does not depend on whether the Terumah itself may be eaten. This is difficult to understand, because if part of the grain was made into Matzah and part became Chametz, when one separates the Chametz as Terumah for the remainder (the Matzah) the Terumah should be valid. Why does the Gemara insist that Chametz cannot be made into Terumah on Pesach?
ANSWER: The SEFAS EMES answers that the fulfillment of the condition of "Reishis she'Sheyareha Nikarin" does not depend on the produce that remains after Terumah has been separated from it. Rather, it depends on the Terumah itself. That is, the Terumah is valid when the remainder would have been permitted to eat had some of the fruit of Terumah not been made into Terumah but remained Chulin (or had the remainder of the dough been ascribed the same Halachic status as the Terumah). "Reishis she'Sheyareha Nikarin" depends only on the Terumah, and not on the rest of the produce. In the case of Chametz on Pesach, Chametz cannot become Terumah because the Chametz itself would not have become permitted had Terumah been taken on its behalf.
(The RASHASH cites the Yerushalmi which asks the question of the Tzelach and gives the answer of the Sefas Emes.)
(It should be pointed out that Rebbi Akiva Eiger's question may be based on the Gemara in Eruvin (37b). The Gemara there discusses another aspect of "Reishis she'Sheyareha Nikarin" and clearly understands it to be a requirement related to the produce that remains, and not to the Terumah itself.)

33b----------------------------------------33b

3) THE JUICE INSIDE A GRAPE
QUESTION: Rebbi Yochanan says that when one squeezes the juice out of grapes that are Tamei, the juice remains Tahor as long as the grapes are less than a k'Beitzah in size. The Gemara explains that Rebbi Yochanan is of the opinion that the liquid inside a fruit is not part of the fruit, and it does not become Tamei along with the fruit.
RASHI (DH Ka'savar Mashkin Mifkad Pekidi) asks why, according to this opinion, the grape which is Tamei does not make the juice inside of it Tamei through contact. Rashi answers that the reason the grape does not make the juice Tamei is because as long as the juice is inside the grape, it does not qualify as a "Mashkeh" (liquid) and thus it cannot become Tamei.
Rashi adds that the juice inside the other grapes cannot join with the juice inside one grape to make a large enough Shi'ur of juice to become Tamei, because the other grapes touch only the outside of the grape and not the juice inside.
Why does Rashi add that the juice of different grapes does not join to make a Shi'ur? Even if the juice of the other grapes combines with the juice of this grape to form a Revi'is, Rashi has already explained that the juice cannot become Tamei because the juice was never outside of the grape and is not yet considered a Mashkeh! Conversely, if the real reason for why the juice inside of a grape does not become Tamei is simply because there is not a Revi'is of juice, and the juice of other grapes cannot combine with the juice in this grape to form a Revi'is, then why does Rashi explain that the juice inside is not considered a Mashkeh? Even if it is a Mashkeh, it cannot become Tamei because there is not enough juice in the grape to be Mekabel Tum'ah! (TZELACH)
ANSWER: The RASHASH and NIMUKEI HA'GRIV explain that the second statement of Rashi is a separate, alternative explanation. Rashi apparently has a doubt whether or not a liquid with a volume less than a Revi'is becomes Tamei. Rashi's two explanations address this doubt. Rashi first suggests that even if a minute amount of liquid can become Tamei, the juice inside a grape is not a Mashkeh at all and cannot become Tamei. Rashi then writes that if a Mashkeh that is less than a Revi'is cannot become Tamei, then that is a more basic reason for why the liquid in a grape does not become Tamei through contact with its skin. In summary, Rashi here is in doubt whether a liquid can be Mekabel Tum'ah (as opposed to transmit Tum'ah) when it is less than a Revi'is, and therefore Rashi gives these two alternative explanations.
TOSFOS in Shabbos (91a, DH Iy) discusses whether food less than a k'Zayis can be Mekabel Tum'ah. (Tosfos' question is similar to Rashi's doubt here with regard to a liquid less than a Revi'is.) Tosfos asserts that Rashi first had one opinion with regard to whether food less than a k'Zayis can be Mekabel Tum'ah, and then Rashi retracted his opinion and taught otherwise. Accordingly, it is reasonable to suggest that Rashi here offers two explanations in order to address both opinions.

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