1)

(a)If the Sheli'ach (of Eruv Chatzeros) is placing his own fruit, he does not need to inform his co-residents what he is doing - because of the principle 'Zachin le'Adam she'Lo Befanav' (meaning even without his knowledge).

(b)But if he is using their fruit, he is obligated to inform them - because, as we have already learnt, if the owner of the fruit is particular about the other residents using his food, then the Eruv is not valid.

(c)The Sabi de'Pumbedisa interpret a 'Mashehu' - as being a Tefach.

2)

(a)Shmuel holds that Shituf Mavo'os requires Zikuy, Eruv Techumin does not - because both are Mishnahs (the former, our Mishnah, the latter, implied in the Mishnah on 82a).

(b)Rav's source is Rebbi Chiya, who is strict by Eruv Techumin, and requires Zikuy.

(c)On the other hand, he holds that Shituf does not need Zikuy in spite of our Mishnah, which holds that it does - because Rav is considered a Tana, who has the power to argues with Tana'im.

(d)Rebbi Chiya might have also been strict with Rebbi Oshaya's daughter - because the Eruv Techumin prepared by her mother-in-law had been placed without her consent (and Eruv Techumin, which restricts the participant from going in the opposite direction, requires his knowledge and consent).

3)

(a)Rav Nachman concludes - that both Shituf Mavo'os and Eruv Techumin require Zikuy.

(b)Rav Yosef maintains that Rav Nachman could not have heard Shmuel's statement ('Eruv Tavshilin Tzarich Lezakos') - because, if he had, he would not have asked the She'eilah.

(c)This is not comparable, Abaye explains, to Eruv Techumin, where Rav Nachman ruled 'Ein Tzarich Lezakos', despite the fact that he knew that Shmuel ruled 'Tzarich' - because, in that case, Rav Nachman was ruling like Rav, who holds 'Tzarich Lezakos' whereas by Eruv Tavshilin, where Rav does not issue a ruling, Rav Nachman would not have ignored the express ruling of Shmuel.

4)

(a)When that non-Jewish guardian of the weapons refused to rent his Reshus for an Eruv - Rebbi Zeira instructed them to rent his Reshus from his wife (even though it is was against her husband's wishes).

(b)Acquiring an Eruv from a man's wife without his consent - only applies when otherwise, his non-participation will forbid them to carry, but not where it will not (e.g. if he lives in a Chatzer between two Mavo'os - when he will not forbid the residents of the one Mavoy, if he is used to using the other).

(c)Shmuel also said 'Echad mi'Bnei Mavoy she'Ragil Lehishtatef im Bnei Mavoy, v'Lo Nishtatef, Bnei Mavoy Nichnasin Le'toch Beiso, ve'Notlin Shitufan Mimenu Ba'al Korcho' - a statement which incorporates both of the above statements.

(d)'Kofin Oso La'asos Lechi v'Korah l'Mavoy' - could be because the Lechi or the Korah are necessary for the protection of the city; it does not however, follow, that we will also force him to participate in the Eruv Chatzeros (like Shmuel).

5)

(a)Even though Rav Chiya bar Ashi permits wood from an Asheirah to be used as a Lechi, it does not follow that he will also permit a Korah (like Resh Lakish) - because, unlike a Lechi, a Korah requires a Shi'ur, and by a beam of an Asheirah we say 'Ketusi Michtas Shi'ureih' (it is as if it has already been burnt, which therefore has no size).

6)

(a)'Nisma'et ha'Ochel, Mosif u'Mezakeh, ve'Ein Tzarich Lehodi'a' - because, since they agreed initially, we can assume that they will not mind if one merely makes up the missing Shi'ur now.

(b)If the Tana is speaking about replacing the missing food with the same kind of food - then why does it confine the Din to 'Nisma'et' (depleted)? Why should it not apply even if the food was completely finished?

(c)The Gemara does indeed, in one answer, establish our Mishnah in this way - and it changes the text accordingly, to read not 'Nisma'et' but 'Nismatmet' (meaning 'finished off').

(d)According to the Gemara's second answer, the Mishnah specifically says 'Nisma'et' - because we are speaking about re-placing it with different kinds of food, which does not require his knowledge only because the food had only become depleted (but had it become completely finished, then replacing them with different kinds of food would have required their knowledge, as the Beraisa specifically writes).

7)

(a)Rebbi Yehudah maintains that, whereas Eruvei Techumin needs the knowledge of all the participants, Eruvei Chatzeros does not - our Tana does not differentiate; according to him, both require their knowledge.

(b)We might have thought that even though the Chachamim in our Mishnah disagree with Rebbi Yehudah, and hold that that applies only with regard to a Chatzer situated between two Mavu'os, where that Chatzer may just want to combine with the second Mavoy, in which case it will be to their disadvantage to combine with the Eruv of the first. Perhaps though, they will agree with Rebbi Yehudah in the Mishnah on 81b (and we will say that he comes to explain the Tana Kama, and not to argue with him), because there, it speaks when there is only one Mavoy, and it is definitely to their advantage to participate in the Eruv. Maybe there, the Chachamim will agree with Rebbi Yehudah that Eruv Chatzeros does not need the consent of all the participants.

(c)In fact though, the Rabbanan disagree with Rebbi Yehudah entirely - because, according to them, the food for the Eruv Chatzeros must be given on the understanding that any of the participants may eat it; for that, the owner's consent is always necessary.

8)

(a)The minimum Shiur for Eruvei Chatzeros ...

1. ... by a large family ... is eighteen Gerogeros (the amount of two meals for one person) - for a family of eighteen or more (even though this will amount to less than one Gerogeres per person).

2. ... by a small family (less than eighteen people) - one Gerogeres per person is required (even though this amounts to less than two meals in total). We go Lekula both ways.

(b)According to Rebbi Yossi - as long as the Eruv consisted of the required amount of food at the outset, it is Kasher even if it later diminished.

9)

(a)According to Rebbi Yehoshua - only whole loaves may be used for Eruvei Chatzeros or Shitufei Mavo'os.

(b)It makes no difference, according to him, whether one loaf is used, or many loaves.