HOW MAY ONE BE ME'AREV ON YOM TOV FOR SHABBOS?
(Rabah bar Rav Chanin): Had Rabah heard the following Beraisa he would have retracted!
(Beraisa): [On Shabbos] one may not walk to the end of his field to see what it requires;
Similarly, one may not to go to the end of the city towards the end of Shabbos in order to go to the bathhouse right after Shabbos.
Rejection: He heard it, yet he did not retract;
There, it is clear why he goes there. Here, it is not clear;
If he is a Chacham, people could assume that he was engrossed in learning [and did not notice where he walks, like Nechemyah brei d'Rav Chanilai (43b)];
If he is an ignoramus, people could assume that he was looking for a lost donkey.
(Rav Yehudah): If one was Me'arev through walking on the first day, he may be Me'arev through walking on the second. If he was Me'arev with bread on the first day, he may be Me'arev with bread on the second;
If one was Me'arev with bread on the first day, he may be Me'arev through walking on the second;
If he was Me'arev through walking on the first day, he may not be Me'arev with bread on the second, for one may not be Me'arev with bread for the first time [on Yom Tov, for Shabbos].
(Shmuel): When one is Me'arev with bread on both days, he must be Me'arev with the same bread.
Support (Rav Ashi - Mishnah): He takes the Eruv on Erev Yom Tov, remains there until nightfall, and takes it home with him. The next day takes it back, and remains there until nightfall, then he may eat it and return.
(Implied Question: All should agree that the Mishnah forbids Hachanah!
Answer): Rabanan (Abaye and Rabah bar Rav Chanin, who challenged Rabah) hold that the Mishnah merely gives practical advice (so one will not lose his Eruv).
THE KEDUSHAH OF THE TWO DAYS OF ROSH HASHANAH
(Mishnah - R. Yehudah): [In Chutz la'Aretz, where people do not hear about which day was made Rosh Chodesh until later in the month,] if one fears that Rosh Hashanah will be [a day later because Elul will be] Me'ubar (30 days; it is normally 29), he can make two [different] Eruvin [because only one of them takes effect, for the day that is really Yom Tov. The other day is Chol, and requires no Eruv];
He can make the Eruv for the first day [of Safek Yom Tov] in the east, and for the second day in the west, or vice-versa;
He can be Me'arev just for the first day, and the second day he is like residents of his city, or vice-versa.
Further, R. Yehudah says that one can stipulate about a basket [of Tevel] on Yom [Tov] Rishon. (He separates the proper amounts, and says 'if today is Chol, these are Terumah and Ma'aseros.') On Yom Sheni he [repeats this declaration and] eats it;
Similarly, if an egg was laid on Yom Rishon, one may eat it on Yom Sheni. (If Yom Rishon was Chol, the Hachanah was on Yom Chol. If Yom Sheni was Chol, we are not concerned for Hachanah.)
Chachamim disagree with R. Yehudah.
R. Dosa ben Hurkinas says, on Rosh Hashanah the Shali'ach Tzibur says '...this day of Rosh Chodesh, be it today or tomorrow. (He says so on the first day. On the second day, he says '...be it today or yesterday');
(Gemara) Question: Who are the Chachamim that disagree with R. Yehudah?
Answer (Rav): It is R. Yosi:
(Beraisa): Chachamim agree with R. Eliezer that if one fears lest Elul be Me'ubar, he can make two Eruvin in opposite directions, one for each day. Alternatively, he can be Me'arev just for the first day or just for the second;
R. Yosi forbids.
R. Yosi: (One may not do Melachah on the 30th of Elul, lest witnesses who saw the new moon come, and Beis Din will make the day Rosh Hashanah.) Don't you agree that if witnesses came after Minchah, we treat the rest of the day like Yom Tov, and also the next day? (This shows that both days have Kedushah!)
Chachamim: This is only so that [in future years] people will not treat the Kedushah of the first day lightly. (Really, if witnesses come after Minchah, the first day is Chol.)
(Mishnah): Further, R. Yehudah says...
We must teach the argument about all three laws;
Had we taught only about an Eruv, one might have thought that here R. Yehudah permits, because he does not actively do anything, but he would forbid the basket of Tevel, for it looks like he fixes it [on Yom Tov];
If we taught only these two cases, one might have thought R. Yehudah permits them because there is no need to decree. However, he would forbid an egg due to fruits that fell from a tree or juice that exuded from food [lest one harvest or squeeze on Yom Tov].
THE TWO DAYS OF YOM TOV OF CHUTZ LA'ARETZ
(Beraisa - R. Yehudah): If one had two baskets of Tevel, on Yom [Tov] Rishon he says 'if today is Chol, this basket is Terumah on (exempts) the other one. If today is Kodesh, my words should have no effect'. The next day, he repeats this declaration, and then he may eat the Chulin.
R. Yosi forbids.
R. Yosi forbids also regarding Yom Tov Sheni of Chutz la'Aretz.
A deer was trapped [by Nochrim] in the Reish Galusa's house on Yom Tov Rishon, and it was slaughtered on Yom Tov Sheni. Rav Nachman and Rav Chisda ate from it, but Rav Sheshes did not.
Rav Nachman: Rav Sheshes does not wish to eat deer meat! (There is no reason to forbid. Yesterday was Chol, or today is!)
Objection (Rav Sheshes): It is forbidden due to Isi's Beraisa!
(Isi - Beraisa): R. Yosi forbids also Yom Tov Sheni of Chutz la'Aretz.
Answer #1 (Rava): Perhaps it means that R. Yosi forbids also Yom Tov Sheni of Rosh Hashanah in Chutz la'Aretz!
Rejection: If so, it should have said 'Yom Tov Sheni in Chutz la'Aretz.' 'Of Chutz la'Aretz' connotes other Yomim Tovim, which are observed for two days only in Chutz la'Aretz.
Answer #2 (Rav Asi): Perhaps it means that R. Yosi makes the two days of Yom Tov of Chutz la'Aretz like the two days of Rosh Hashanah according to Chachamim, who permit!
Rav Sheshes (to Rabah bar Shmuel): Did you learn anything about the two Kedushos?
(Rabah bar Shmuel - Beraisa): R. Yosi agrees about the two days of Yom Tov of Chutz la'Aretz.
Rav Sheshes: If you see Rav Nachman and Rav Chisda, do not tell them. (I am ashamed that I erred.)