1) "ASEH DOCHEH LO TA'ASEH"
QUESTION: The verse teaches that one is forbidden to break the bone of the Korban Pesach even if he wants to get to the marrow in order to eat it. Had the verse not stated this explicitly, we might have thought that one is permitted to break the bone in such a case, because the Mitzvas Aseh to eat the Korban Pesach overrides the Lo Ta'aseh not to break the bone.
Why would we have thought that one is permitted to break the bone because of "Aseh Docheh Lo Ta'aseh"? In order for an Aseh to override a Lo Ta'aseh, the Aseh and the Lo Ta'aseh must be done at the same time ("b'Idnei"). At the moment that one fulfills the Aseh, he must do the Lo Ta'aseh as well in order for the Aseh to override it. If he does the Lo Ta'aseh now but the Aseh later, he is not permitted to transgress the Lo Ta'aseh. For example, if a Kohen has a Nega (a leprous mark which disqualifies him from performing the Avodah), he may not transgress the prohibition against cutting off a Nega in order to fulfill the Mitzvah of performing the Avodah, because he does not perform the Avodah at the moment that he cuts off the Nega (Shabbos 133b). (TOSFOS DH k'she'Hu Omer; see also Insights to Pesachim 35:2 and 47:3.)
ANSWERS:
(a) The PISKEI TOSFOS in Zevachim (97b, #69) explains that when it is impossible to fulfill the Aseh without transgressing the Lo Ta'aseh, one may transgress the Lo Ta'aseh even before he actually fulfills the Aseh.
This opinion seems to contradict the Halachah in the case of the Kohen with a Nega, because in that case it is impossible for the Kohen to perform the Avodah without removing the Nega, and yet he still is not allowed to cut it off.
Perhaps the Piskei Tosfos means that when that type of Mitzvah will never be fulfilled unless one does a Lo Ta'aseh, the Aseh overrides the Lo Ta'aseh even when the Aseh is not fulfilled at the same time that the Lo Ta'aseh is done. If the Mitzvah to eat the Pesach applies to the marrow inside the bone, then that Mitzvah could never be fulfilled without breaking the bone. A Kohen who has a Nega, though, can fulfill the Mitzvah to perform the Avodah at a different time, or have another Kohen do it for him now. It is merely coincidental that the Kohen has a Nega when it is his turn to perform the Avodah. In the case of marrow inside a bone of the Korban Pesach, the Mitzvah to eat the Korban Pesach in its entirety will always necessitate breaking the bone.
(b) RAV YAKOV EMDEN answers this question based on the words of the RAN cited by the NIMUKEI YOSEF in Bava Metzia (end of 16a of the pages of the Rif). The Gemara in Bava Metzia (30a) implies that if only a Lo Ta'aseh would prohibit a Kohen from entering a cemetery (instead of an Aseh and a Lo Ta'aseh), then there would be grounds to permit a Kohen to enter a cemetery in order to retrieve a lost object and perform the Mitzvah Aseh of Hashavas Aveidah. The Aseh of Hashavas Aveidah would override the Lo Ta'aseh which prohibits a Kohen from becoming Tamei by entering a cemetery.
The Rishonim there ask why the rule of "Aseh Docheh Lo Ta'aseh" would apply in such a case. The Kohen transgresses the Lo Ta'aseh immediately when he enters the cemetery, but he does not fulfill the Aseh of Hashavas Aveidah until later, when he returns the lost object.
The Ran answers that the Mitzvas Aseh involves all of the actions that the Kohen must do in order to retrieve the lost object. Since his first step into the cemetery is part of the fulfillment of the Mitzvah, the Mitzvah and the Lo Ta'aseh are considered as though they are being done at the same time, even though the Mitzvah is completely fulfilled only after the object is returned to its owner.
Similarly, in the case of the Gemara here, when one breaks the bone of the Korban Pesach to get the marrow, he is considered to be involved in the process of fulfilling the Mitzvah to eat the marrow. Since he breaks the bone during that process, the principle of "Aseh Docheh Lo Ta'aseh" should apply.
(The comparison between the case of the lost object in a cemetery and the case of breaking a bone to get the marrow is questionable. The Ran maintains that in the case of the lost object, the Mitzvah is not merely to place the lost object into the hands of the rightful owner. Rather, the Mitzvah is the involvement in returning the lost object from the moment that one finds it and moves towards it to pick it up. That is why one who turns away from the lost object after he sees it transgresses a Mitzvas Aseh (Bava Metzia 26a). In the case of the Korban Pesach, however, the Mitzvah is solely to eat the meat of the Pesach. Efforts that one makes in order to get the meat are not considered part of the fulfillment of the Mitzvah. One must perform an act of eating in order to fulfill the Mitzvah.)

85b----------------------------------------85b

2) TWO COMMANDMENTS IN ONE VERSE -- ONE PLURAL AND ONE SINGULAR
QUESTION: The Gemara discusses the prohibition against taking the meat of the Korban Pesach out of its designated place. The Torah requires that the members appointed to eat from one Korban Pesach eat the Korban together in the same house, and it prohibits them from taking the meat out of the house (Shemos 12:46). The Gemara derives from the verse that one is prohibited from taking the meat of the Korban even from one Chaburah to another Chaburah.
The prohibition against taking the meat of the Korban Pesach out of the house is expressed in the verse, "In one house it shall be eaten. You shall not take (Lo Totzi) any of the meat outside of the house, and you shall not break (Lo Tishberu) any bone in it" (Shemos 12:46).
When the verse teaches the prohibition against taking the meat out of its place, it says, "Lo Totzi," in the singular form. When it teaches the prohibition against breaking a bone, however, it says, "Lo Tishberu," in the plural form. Why does the verse change from the singular form ("Lo Totzi") to the plural form ("Lo Tishberu")?
ANSWERS:
(a) RAV ZALMAN VOLOZHEN (cited by Sefer Toldos Adam) explains that according to the Yerushalmi, the Torah prohibits one from breaking a bone that has already been broken. However, the Torah does not prohibit one from taking meat of the Korban Pesach to another house if it has already been removed from its original house.
This is why the verse expresses the prohibition against breaking a bone in the plural form. "Lo Tishberu" alludes to the fact that the prohibition applies to more than one person; even if you are the second person to break this bone, you shall not break it.
In contrast, the verse expresses the prohibition against taking the meat out of the house in the singular form, because that prohibition applies only once, to the first person who removes the meat from its place.
(b) The TORAH TEMIMAH gives an ingenious answer based on the Gemara here. Rebbi Ami says that one who takes the meat of the Korban Pesach from one Chaburah to another transgresses the prohibition only when he sets it down. He derives this from the laws of Shabbos. In order to be liable for the Melachah of Hotza'ah on Shabbos (carrying from Reshus ha'Yachid to Reshus ha'Rabim), one must do both an act of Akirah (moving the object from its place) and an act of Hanachah (placing the object to rest). If one does only part of the act of Hotza'ah, he is not liable. The Gemara in Shabbos (92b) derives this law from a verse (Vayikra 4:27) which teaches that in order to be liable for performing a Melachah on Shabbos, one must do the entire Melachah himself. If he does one part of the Melachah and someone else does the rest, neither person is liable, because each person has done only half of the act.
RASHI here (DH d'Avad Lei) explains that this rule applies to all Chiyuvei Chatas and Chiyuvei Kares. It does not apply to Isurei Lav -- except for one, the Lav of "Lo Totzi," the prohibition against taking the meat of the Korban Pesach out of its designated place. Since the Torah calls it a prohibition of "Hotza'ah," it compares it to the prohibition of Hotza'ah of Shabbos, even though the Hotza'ah of the Korban Pesach is only an Isur Lav and the Hotza'ah of Shabbos is a Chiyuv Chatas.
According to Rashi's explanation, if one person does the Akirah of the meat of the Pesach and another person does the Hanachah, neither one will be liable, because the Lav of "Lo Totzi" is compared to the Melachah of Hotza'ah on Shabbos.
This is alluded to by the precision of the verse. When the verse teaches the prohibition against breaking the bone of the Korban Pesach, it says "Lo Tishberu" in the plural form, because even if two people do the act of breaking a bone together, they will be liable; the rule that one person must do the act in order to be liable does not apply to ordinary prohibitions such as this one. In contrast, the prohibition against taking the meat out of the house is compared to the Melachah of Hotza'ah on Shabbos, and one is liable only when he does the act by himself, but not when he does it with somebody else. Therefore, the verse says, "Lo Totzi," in the singular form!
3) THE "AGAF"
OPINIONS: The Korban Pesach must remain within the boundaries of Yerushalayim. If it is taken out of Yerushalayim, it becomes Pasul. When the Mishnah defines the boundaries of Yerushalayim, it refers to the "Agaf" as the boundary. The Agaf is the area beneath the door of each gate of the city. It is the part of the floor which the door covers when it is closed (this area can be quite large, considering the thickness of the doors of the wall of the city).
The Mishnah first says that the Agaf is considered part of the inside of the city. The Mishnah then says that it is considered part of the outside of the city. The Gemara explains that the Mishnah means that with regard to the gates of the Azarah and objects that may not be taken out of the Azarah, the Agaf of the gates of the Azarah is considered part of the inside of the city. With regard to the gates of Yerushalayim and objects that may not be taken out of Yerushalayim, the Agaf of the gates of Yerushalayim is like the outside of the city and has no sanctity.
Rav Yehudah in the name of Rav says that these guidelines also apply to Tefilah, and the area of the Agaf is considered part of the inside. Rebbi Yehoshua ben Levi argues and says that with regard to Tefilah, "even an iron partition does not separate between the Jewish people and their Father in Shamayim." To which Halachah of Tefilah does this discussion refer?
(a) RASHI (DH v'Chen l'Tefilah) says that one who stands on or within the area of the Agaf may be included in a Minyan for Tefilah. If he stands outside of the entranceway, he does not join to make a Minyan, according to Rav. Rebbi Yehoshua ben Levi says that he may be included in the Minyan even when he stands outside of the entranceway.
(b) TOSFOS (DH v'Chen l'Tefilah) argues with Rashi and says that everyone agrees that a person who stands outside of the room does not join to make a Minyan, as the Gemara in Eruvin (92b) implies. Rather, the Gemara here is discussing a case where there is already a Minyan inside the room, and the person standing outside (or on the Agaf) wants to respond to Kedushah or Kaddish, or fulfill the obligation to pray with a Minyan (Me'iri). Rav maintains that he may respond to Kedushah and Kaddish only if he is standing on or within the Agaf. Rebbi Yehoshua ben Levi permits him to respond even if he is standing outside.
The ME'IRI suggests that Rashi maintains that the Gemara here does not disagree with the Gemara in Eruvin. The Gemara here is discussing the Halachah in a case of an individual who is in the outer half of the doorway. The Gemara in Eruvin rules that he may be counted together with the nine people inside the house. When the Gemara says that "even an iron partition does not separate" between the people in the house and the person outside, it does not mean that no partition can ever separate them. Rather, it refers only to the specific case of a person who is in the outer half of the doorway. Although the door is closed, since it will be opened soon it cannot separate the person outside the door from those inside. It is not comparable to a permanent partition.

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