Rav Nehemya Taylor
Torani Advisor to Torah MiTzion

Yom Tov Sheni, Part 1

After careful consideration, we have decided to take a break from the subject of bishul akum and its ramifications, and to focus on a different problem which shlichim (emissaries) from Israel often face — the issue of Yom Tov Sheni (the second day of Yom Tov in the Diaspora). In this article, the first of a series, we will trace the development of Yom Tov Sheni.
The first commandment that the Jews receive as a nation is sanctifying the month (kiddush hachodesh). According to the Rambam, one component of this commandment is the requirement to let everyone know that the month had been sanctified:

It is a positive Torah commandment for the Beit Din to calculate and evaluate whether the moon has been seen, by examining the witnesses. When the Beit Din is satisfied, it sanctifies the month. Then it must notify the rest of the nation when Rosh Chodesh is, so that they will know when the holidays are. This is in accordance with the verse (Vayikra 23:2), “which you shall proclaim as sacred occasions,” and the verse (Shemot13:10), “You shall keep this institution at its set time” (Rambam, Hilkhot Kiddush HaChodesh 1:7).

The Lechem Mishneh supplies the source of this ruling:
At the end of the first chapter of Rosh HaShanah (22a), it is taught: “We desecrate the Sabbath to testify about the month, as it says (Vayikra 23:4), ‘These are the set times of the Lord, the sacred occasions, which you shall proclaim, each at its appointed time.'” The Rambam derives from here that it is a mitzvah to notify the nation, for the Talmud implies that “proclaim” includes sending the messengers (Rabbi Avraham di Boton, Lechem Mishneh, Kiddush HaChodesh 1:7, s.v. vayishalchu).

We see from here that the Beit Din which sanctifies the month is obligated to inform the entire nation when each month begins, in order to enable them to sanctify the holidays at the proper time.

At first, the notification was made by lighting torches, as it says in the Mishnah (Rosh Hashanah 22b) and in the Rambam:
In earlier times, when the Beit Din sanctified the month they would light torches on the mountaintops so those living at a distance would know. When the Kutim (Samaritans) sabotaged this by lighting torches themselves (at the wrong time) in order to mislead the people, the Beit Din instituted the messenger system (Rambam, 3:8).

It seems that until the Kutim began their sabotage, the people relied on the torches. Anyone who knew they had sanctified the month via the torches also knew exactly when the holidays would be. However, anyone who, for whatever reason, and in whatever place, did not know about the sanctification of the month, would observe Yom Tov Sheni. We can conclude this from the Responsa of the Geonim:
Rabbeinu Saadia Gaon z”l said in his commentary that there is no doubt that God originally commanded His servant Moshe (who then told Israel) that in the Land they would have one day of Yom Tov and outside of the Land they would have two days, and thus it has always been (Teshuvot HaGeonim, Mussafia edition (Lyck, 1864), #1).

Later on, the responsum adds:
Since Israelbehaved thus in accordance with the instructions of the prophets, it has become obligatory on all living outside the Land to continue, as if it were a Divine commandment. And perhaps this behavior was already instituted in the days of Joshua son of Nun.

We can conclude from the words of Rabbeinu Sa’adiah Gaon, Rav Hai Gaon, and other Geonim that there was a very early ordinance mandating two days of Yom Tov for people who lived outside of Israelin places where they did not know when the month had been sanctified.

This was the first historical stage, and it ended in the time of Rabbi Yehudah HaNasi as a result of the sabotage of the Kutim. According to the Jerusalem Talmud (Rosh HaShanah, beginning of Chapter Two), “Who abolished the torches? Rebbi (i.e., Rabbi Yehudah HaNasi) abolished the torches.” Instead of torches, he established that the way to notify those outside the land would be with messengers. As the Rambam states, Wherever the messengers reached, people would celebrate the holiday for one day, as it says in the Torah. Places that were too far for the messengers to reach observed two days because of the uncertainty, since they did not know which day the Beit Din sanctified as the beginning of the month (Rambam, 3:11).

During this second stage, before there was a general directive about observing Yom Tov Sheni outside the Land, Rashi (Beitzah 4b) suggests that if an individual knew the procedure of intercalating and the exact ways to calculate when the month should be sanctified, he would not have to observe Yom Tov Sheni. This question first comes up in Pesachim 51b-52a. Rashi there understands the Gemara as saying that in an inhabited area, such a person would still be required to observe Yom Tov Sheni, since that is the custom of the people there, and it is forbidden to deviate from local custom. In the desert, though, where there are no people, he would not be required to observe it. However, Rabbeinu Tam disagrees with this understanding (Tosafot there) and maintains that this Gemara is speaking of a place where the messengers did reach, and the discussion is about something entirely different. In any case, we see that, according to Rashi, during the second stage a sage who knew the procedure of intercalating was permitted to keep only one day of Yom Tov even outside the Land.

The third stage was the generation of Rabbi Elazar ben Pedat, i.e., the second generation of Amoraim. Even though they still established the months according to calculations and sanctification by the Beit Din, there was already an absolute rule. The Talmud states (Beitzah 4b), “Be careful to keep the custom of your ancestors because a time may come when there are anti-religious persecutions, and all will be confused.” (In other words, they sent an admonition from the Landof Israelsaying to keep Yom Tov Sheni, because the authorities may forbid sanctifying the month, and this could lead to chametz being eaten on Passover, and the like.) From then on, they did not keep Yom Tov Sheni because of uncertainty, but rather because they were afraid lest, as a result of anti-religious decrees, they would forget the procedures of sanctification, and would make a mistake when calculating the start of the new month.

The fourth period started with Hillel the Second, who established the calendar which became the official calendar for all of Israel. As the Rambam explains:

When did all of Israelbegin following this calculation? From the end of the time of the Talmudic Sages, when the land was destroyed and there was no regular Beit Din. However, in the days of the Mishnaic Sages and the early Amoraic Sages until the time of Abaye and Rava, everyone had relied on what was done in the Landof Israel(Rambam, 5:3).

From then on, the nation decided that it would follow the custom of its ancestors even though it was originally based upon an uncertainty which no longer existed.

We have given an overview of the halakhic and historic development of Yom Tov Sheni. God willing, in upcoming articles we will deal with the practical side of this topic, specifically with relation to Israelis who are living abroad.