Correction to yesterday’s Halacha entitled: "The Laws of Candle Lighting When Yom Tov Occurs on Shabbat and Sunday". The transcription had an error. Ladies should recite "Baruch Ha'mavdil Ben Kodesh Le'Kodesh" after Shabbat ends, when lighting candles for Yom Tov. (We apologize about the error, and are grateful to so many who emailed us about this issue.)
A person who moves from the Diaspora to Israel observes only one day of Yom Tob just like native residents of Israel. Even though he had been observing two days of Yom Tob his entire life, once he becomes a resident of Israel he observes only one day.
The question arises regarding the status of a person who moved to Israel but is unsure whether he will remain there permanently. He moved to Israel with the intention of waiting to see how his situation unfolds in terms of housing, employment and so on, before making a final decision to remain. His plan is to return to his original place of residence if things do not work out for him in Israel, and to remain if things do work out. Do we consider a person in this situation a resident of Israel, such that he observes only one day of Yom Tob, or as a resident of his country of origin, in which case he must observe two days, as he has until now?
The work "Yom Tob Sheni Ke’hilchato" records a debate among the Halachic authorities surrounding this issue. Rav Yosef Shalom Elyashiv (contemporary) claims that since this is a situation of "Safek" (uncertainty), the individual in question should observe only one day of Yom Tob. If he observes two days, but ultimately decides to remain in Eretz Yisrael, such that he had been required to observe only one day, then he violates the Torah prohibition of "Bal Tosif," which forbids adding onto Misvot. In order to avoid this transgression, a person in this situation of uncertainty should observe only one day of Yom Tob, rather than risk observing an unwarranted second day.
Rav Moshe Feinstein (Russia-New York, 1895-1986), however, ruled differently. He claimed that a resident of the Diaspora retains this status until he moves to Israel with the definitive intention of settling there permanently. As long as the individual leaves open the option of returning to his country of origin, and has not reached a final decision to reside in Israel, he retains his prior status as a "Ben Hutz La’aretz" (Diaspora resident), and must therefore observe two days of Yom Tob. According to Rav Moshe, one does not change his status and become a resident of Israel with respect to Yom Tob observance until he has moved there and definitively decided to live there.
This was also the ruling of Rav Abraham Yishaki, in his work of responsa Zera Abraham (Orah Haim 12), where he writes that as long as one has not definitively established residence in Israel, he retains his status as a "Ben Hutz La’aretz." It is worth mentioning that the Hid"a (Rav Haim Yosef David Azulai, 1724-1806) describes Rav Abraham Yishaki as the greatest sage of his generation, and thus his Halachic rulings certainly carry significant weight.
Indeed, Hacham Ovadia Yosef, in his work Hazon Ovadia – Hilchot Yom Tob (p. 130), follows the ruling of the Zera Abraham and Rav Moshe Feinstein. He writes (listen to audio recording for precise citation) that if a person moved to Israel but has not definitively decided to remain there permanently, he is still considered a resident of the Diaspora and observes two days of Yom Tob.
It should be noted that this is not the Halacha in the case of an unmarried Yeshiva student who spends a year studying in Eretz Yisrael. The Hid’a ruled that young, unmarried Yeshiva students from the Diaspora who spend time studying in Israel should observe only one day of Yom Tob, given the possibility that they will find a wife and settle permanently in Israel. This view is accepted by Hacham Ovadia Yosef. At first glance, this ruling may appear to contradict the aforementioned position of Hacham Ovadia, that a person who moves to Eretz Yisrael but has yet to decide upon permanent residence observes two days. Seemingly, this case should be no different from the situation of an unmarried Yeshiva student.
In truth, however, the two situations differ significantly from one another. In the case of an unmarried Yeshiva student, he does not have a permanent residence in either location. As he lives away from his parents’ home but has yet to marry, he is not considered to be a permanent resident of the Diaspora or of Eretz Yisrael. Therefore, when determining his status vis-ŕ-vis Yom Tob, Halacha looks at his current location, and he therefore observes only one day like residents of Israel. However, a person that has been living in America, for example, with a family, home and job, is considered to have permanent residence in America until he moves to Israel with the definitive intention of remaining there. Unlike the Yeshiva student, the family has established permanent residence in the Diaspora, and this status is undone only once they definitively move to Israel.
Summary: If a person who has been living in the Diaspora moves to Israel with the intention of trying out life there before deciding to reside there permanently, he observes two days of Yom Tob, even though he is in Israel, since he has not yet changed his permanent residence. However, a young, unmarried Yeshiva student from the Diaspora who is studying in Israel observes only one day of Yom Tob.