[In updating the Insights to the Daf on Chulin, we removed the Halachic

issue of Yom Tov Sheni, because it is not relevant to the conduct of Rebbi

Zeira discussed here in the Gemara, and because we discuss the issue at

length elsewhere (see Insights to Pesachim 51 and 52), and because the

issue of Yom Tov Sheni involves more issues than just following the Minhag

of the place.]

We know that when the Beis ha'Mikdash was standing and the Sanhedrin convened, the new month was established by the Beis Din, based on the testimony of witnesses who saw the new moon. Messengers were then dispatched to inform Jews in all other places which day was established as Rosh Chodesh (either the thirtieth day or the thirty-first day after the previous Rosh Chodesh), so that they would know when to observe the festivals. Places that were too far away for the messengers to reach before the Yom Tov arrived (the 15th day of Tishrei (Sukkos) or the 15th day of Nisan (Pesach)) observed two days of Yom Tov out of doubt.

In the year 4118 (358 C.E.), a set calendar was established, sanctifying all future months based on the astronomical calculations of determining the new month. This was done due to the concern that the Sanhedrin would no longer be able to sanctify the months due to the deteriorating situation in Israel. As a result, Jews all over the world celebrate the festivals based on this fixed calendar. However, places that previously had observed two days of Yom Tov continue to do so, because of a rabbinical enactment. (This enactment, as the Gemara explains in Beitzah 4b, was instituted due to the concern that "the government might make a decree and people will come to err." This means that if the governing power in a country one day forbids Torah study (as indeed happened numerous times in history), the Jews might forget how to calculate the Jewish calendar. Consequently, they might mistakenly declare Adar (which normally has 30 days) to have 29 days, begin Pesach one day early, and eat Chametz on what is actually the last day of Pesach. The sages therefore enacted that the Jews in Chutz la'Aretz must continue to observe two days of Yom Tov. See Rashi to Beitzah 4b.).

How, though, are Jews who visit Israel for Yom Tov supposed to conduct themselves?

According to most authorities, a Jew who visits Israel must observe all the laws of the second day of Yom Tov. This is the view of the Beis Yosef (in Avkas Rachel #26), which is accepted by the Sha'arei Teshuvah (OC 496), Birkei Yosef (ibid.), She'elas Ya'avetz (2:168), Pe'as ha'Shulchan (Hilchos Eretz Yisrael 2:15), and Mishnah Berurah (496:13).

Most contemporary Poskim follow this view, including Rav Moshe Feinstein zt'l (Igros Moshe OC 4:101), the Minchas Yitzchak (4:1-4, 9:54), Sha'arei Yitzchak, citing the Chazon Ish and Tchebiner Gaon. This is also the ruling of Rav Shlomo Zalman Auerbach zt'l, Rav Elyashiv shlit'a, Rav Shmuel HaLevi Wosner shlit'a, and Rav Chaim Pinchas Sheinberg shlit'a.

A second opinion maintains that a visitor to Israel follows the practice in Israel and observes only one day of Yom Tov. This is the view of the Chacham Tzvi (#167), whose view is recorded by the Shulchan Aruch ha'Rav (OC 496; this is why Lubavitch Chassidim have the practice to observe one day of Yom Tov when visiting Israel). The logic of the Chacham Tzvi is that the obligation to keep two days of Yom Tov depends on the place where the person spends Yom Tov, and not on the place where the person permanently resides. (Note that the Ya'avetz, Rav Yaakov Emden, who was the son of the Chacham Tzvi, argues with his father's opinion (see above). On the basis of this, Rav Elyashiv says that the opinion of the Chacham Zvi may no longer be relied upon.)

A third opinion maintains that a visitor to Israel must observe the stringencies of both Yom Tov and an ordinary day. (This opinion is misleadingly referred to as "one and a half days" of Yom Tov.) This is the view of Rav Shmuel Salant, as recorded by Rav Y. M. Tukachinsky in Ir ha'Kodesh v'ha'Mikdash (3:19:11). In practice, this means, among other practical ramifications, that (a) one should recite the weekday Shemoneh Esreh on the second day of Yom Tov, and not recite Kidush (and he should hear Havdalah from a Ben Eretz Yisrael); (b) one should refrain from all Melachah that is forbidden on Yom Tov; (c) on the second night of Pesach, one should not make a second Seder (but one who wants to eat Matzah and Marror may do so but without reciting the blessings of "Asher Kideshanu...," and one may drink the four cups of wine and recite the Hagadah, but without the blessing at the end of the Maggid section); (4) following the seventh day of Pesach, one should not eat Chametz nor do any Melachah, but he should wear Tefilin and recite the weekday Tefilos.

The overwhelming majority of Poskim follows the first view. Very few follow the third view, and there are certain groups that follow the second group. Like everything else, one's decision which opinion to follow must be based not considerations of convenience and self interest, but on the consideration of how best to serve Hash-m.

Y. Shaw

D.A.F.

Jerusalem, Israel