IS ZIKUY NEEDED FOR ERUV?
Question (against Rav Yehudah, who said that one lifts the barrel a Tefach off the ground - Beraisa): To be Mishtatef, one brings a barrel of wine, oil, dates, figs, or other produce;
If he owns it, he is Mezakeh (acquires) for everyone. If the Bnei Mavoy jointly own it, he must inform them;
[To be Mezakeh] he lifts it any amount off the ground.
Answer: 'Any amount' means a Tefach. (Rashi - we do not require three Tefachim like for regular Kinyanim.)
(Rav): One need not be Mezakeh for Shituf;
(Shmuel): One must be Mezakeh;
(Rav): One must be Mezakeh for Eruv Techumim;
(Shmuel): One need not be Mezakeh.
Question: We understand Shmuel. Our Mishnah teaches that one must be Mezakeh for Shituf, and the Mishnah of [how to make] Eruv Techumim does not mention Zikuy;
However, what is Rav's reason?
Answer: Tana'im argue about whether or not Zikuy is needed:
(Rav): A case occurred in which R. Oshaya's daughter-in-law went to the bathhouse on Erev Shabbos and did not return before dark. Her mother-in-law was Me'arev for her (Tosfos - Eruv Chatzeros; Rashi - Eruv Techumim). R. Chiya disqualified the Eruv.
R. Yishmael b'Rebbi Yosi: Why are you stringent? My father taught that we are lenient about Eruvin whenever possible!
Question: Was her mother-in-law Me'arev with her own food, and R. Chiya was Posel because she was not Mezakeh;
Or, did she Me'arev with the daughter's food, and R. Chiya was Posel because the daughter did not authorize it?
Answer (R. Yakov citing R. Yochanan): It was the mother-in-law's food, and she did not Mezakeh.
R. Zeira asked R. Yakov, the son of Bas Yakov to ask this of R. Yakov bar Idi. R. Yakov bar Idi gave the same answer.
(Rav Nachman): The Halachah is, Zikuy is required for Eruv Techumim, Eruv Chatzeros and Shituf.
Question (Rav Nachman): Does Eruv Tavshilim require Zikuy?
Question (Rav Yosef): Why does he ask? Didn't he hear Rav Nachman bar Ada say that Shmuel requires Zikuy?!
Answer (Abaye): Obviously, he did not hear it! Had he heard it, he would not ask!
Objection (Rav Yosef): Regarding Eruv Techumim, even though Shmuel does not require Zikuy, Rav Nachman does! (Here also he could argue with Shmuel.)
Answer (Abaye): There is different, for Rav argues with Shmuel. Rav Nachman adopts the stringencies of both of them;
Here, no one argues with Shmuel. Had Rav Nachman heard Shmuel's opinion, he would not have asked!
TAKING AN ERUV WITHOUT RESHUS
A Nochri (the overseer of the weapons of the city) in R. Zeira's area refused to rent his Reshus. His neighbors asked R. Zeira if they can rent from his wife.
(R. Zeira): Reish Lakish taught that a wife can be Me'arev without her husband's Da'as (awareness. Eruv only applies to Yisraelim, but likewise, a Nochris can rent without her husband's Da'as.)
The same question came in front of Rav Yehudah bar Oshaya and Rav Masnah; they did not know. Rav Yehudah was asked, and he answered in the name of Shmuel, like Reish Lakish.
Question (Beraisa): If a woman was Me'arev or Mishtatef without her husband's Da'as, it is invalid.
Version #1 (Rashi) Answer: The Beraisa discusses when he does not forbid the Chatzer or Mavoy. (E.g. if a Chatzer is open to two Mavo'os, and it normally uses one of them, it does not forbid the other.) When he forbids, Reish Lakish and Shmuel permit [to rent from his wife without his Da'as].
Support: If we would not say so, Shmuel contradicts himself!
(Shmuel): If a member of a Mavoy usually is Mishtatef (Me'iri - or usually uses the Mavoy) and now he was not Mishtatef, the Bnei Mavoy may enter his house and take Shituf [with his wife's consent], even against his will. (Me'iri - even if he previously protested, we assume that a man desires what his wife does. However, if he protests against her Shituf, it is invalid.)
Version #1 (Tosfos) Inference: One may take from his wife only if he usually is Mishtatef (for then he forbids). Otherwise, one may not.
Version #2 (Rosh) Inference: His wife's consent helps only if he usually is Mishtatef (this applies when he does not forbid. When he forbids, one may take the Shituf without his consent even if he is not usually Mishtatef.)
Support (Beraisa): We force one to make a Lechi or Korah for a Mavoy.
Version #1A (our text, Rashi) Rejection: That is when there are no Mechitzos. (We force one to make a Lechi or Korah to help guard the Mavoy. Otherwise, we cannot force.)
Version #1B (Tosfos) Rejection: That refers to Mechitzos. (A Lechi or Korah is a Mechitzah, whether he made it willingly or was coerced. Eruv works due to Kinyan or residence, so it requires consent.)
Version #2 (Gra) Rejection: Beis Din is different. (It can force, but Bnei Chatzer cannot.) (end of Version #2)
(R. Chiya bar Ashi): An Asherah may be used for a Lechi.
(Reish Lakish): An Asherah may be used for a Korah.
Reish Lakish permits a Korah. All the more so he would permit a Lechi;
R. Chiya permits a Lechi, but he would not permit a Korah. Since an Asherah must be burned, it is as if it is ashes, so it does not have the required Shi'ur. (A Lechi must be 10 Tefachim tall, but the width and thickness do not matter. Chachamim gave more importance to a Korah, which must be a Tefach wide and strong enough to hold a half-brick. Something that must be burned is not so important.)
ADDING TO AN ERUV
(Mishnah): If the food for the Eruv was Nisma'et (diminished below the Shi'ur), one must be Mezakeh more [before the next Shabbos]. He need not inform the others;
If new residents joined the Chatzer, one must add and be Mezakeh more food [of his own. Alternatively, he can be Me'arev with their food], and he must inform them (Rashi. R. Yehonason - if the Chatzer opens to only one Mavoy, even when new residents join, he need not inform them. It is a Zechus that they not forbid themselves and the Mavoy.)
When there are many people in the Mavoy, the Shi'ur is two meals (altogether). When there are few people in the Mavoy, the Shi'ur [for bread] is k'Grogeres (the size of a dried fig) for each person;
R. Yosi says, this applies when one is Me'arev initially. Any remnant of an Eruv is valid;
Chachamim required Eruvei Chatzeros [when there is Shituf Mavo'os] only to ensure that children [who do not see what happens in the Mavoy] will not forget the Mitzvah of Eruv.
(Gemara) Question: What is the case?
Suggestion: He adds food of the same kind [that the Eruv consisted of].
Rejection: If so, this is not only if the Eruv was diminished [below the Shi'ur]. Even if it was totally finished; he need not inform the others!
Answer: He adds a different food.
Objection: If so, even if the Eruv was only diminished he must inform the others!
(Beraisa): If the food was totally finished:
If he adds more of the same, he need not inform the others;
If he adds a different food, he must inform the others. (We assume that the same applies even if it was diminished. The Beraisa said 'totally finished' to teach that even then, he can add the same food without informing them.)
Answer #1 (and Defense of suggestion (d:1)): Really, he adds food of the same kind. In the Mishnah, 'Nisma'et' really means Nismatet (it was finished).
Answer #2: Indeed, he adds a different food. The Beraisa requires informing the others only if the Eruv was finished.
(Mishnah): If new residents joined the Chatzer, one must add and be Mezakeh [he must inform the others].
(Rav Shizbi): This teaches that Chachamim (our Tana, who is also the first Tana of the coming Mishnah) argue with R. Yehudah (i.e. R. Yehudah comes to argue, not to explain):
(Mishnah - R. Yehudah): This (one cannot be Me'arev for another without his Da'as) only applies to Eruv Techumim [for his gain in one direction (the extra distance he may walk) he loses in the opposite direction], but one may be Me'arev Eruvei Chatzeros for someone even without his Da'as.
Objection: It is obvious that they argue!
Answer: One might have thought that [there is no argument;] our Mishnah discusses [only] a Chatzer between two Mavo'os. (If he is Me'arev with one, the other is forbidden to him), but [all agree that] if it opens only to one Mavoy, one may be Me'arev without their Da'as. He teaches that this is not so. (Our Mishnah discusses one Mavoy. Even so, Chachamim require their Da'as.)
(Mishnah): [When there are many people in the Mavoy,] the Shi'ur...
Question: What is considered many?
Answer (Rav Yehudah): Eighteen people is considered many.
Objection: Is 18 considered many, but more is not?!
Correction: Rather, 18 or more [is considered many].
(Rav Yitzchak brei d'Rav Yehudah citing Rav Yehudah): If we would divide two meals among the people and it would be less than k'Grogeres for each, this is many. Two meals suffice for all of them;
Less people than this is few. A k'Grogeres is needed for each person.
He teaches, by the way, that two meals is (R. Yehonason's text - less than) 18 k'Grogeros. (According to our text, technically, 18 is called few (Rashash). Even so, in any case the Shi'ur for 18 equals two meals.)
WHAT MAY BE USED FOR AN ERUV
(Mishnah - R. Eliezer): One may be Me'arev or Mishtatef with anything except for water and salt;
R. Yehoshua says, an Eruv must be a loaf;
Even if a partial loaf is the volume of a Se'ah (12 liters), one may not be Me'arev with it;
Even if a loaf is the volume of an Isar (a small coin worth about eight Perutos), one may be Me'arev with it. (Rambam - one suffices for Eruvei Chatzeros. The Shi'urim in the previous Mishnah are for Shitufei Mavo'os. Rashi - one must be Me'arev with enough loaves to comprise a Shi'ur. Tosfos R. Peretz - it comprises the Shi'ur. It is very long, just its width is only k'Isar. Alternatively, it is worth only an Isar. R. Yehonason - it must be k'Grogeres, the amount that each person must give for the Eruv.)