The practice of observing two days of Rosh Hashanah, known as yoma arikhta (“one long day”), has its roots in the complexities of the Jewish calendar and the historical development of the holiday’s observance. Let’s explore the issue step-by-step, from the fundamental calendaric principles to the historical imposition of the two-day observance.
Today, Rosh Hashanah is observed for two days universally. Even in Israel, where one might argue for a single-day observance based on calendaric certainty, this was not the case in history.
The Jewish Calendar and Rosh Chodesh
The Jewish calendar is a lunar calendar, with months beginning with the sighting of the new moon. In ancient times, the Sanhedrin (the supreme Jewish court) in Jerusalem was responsible for sanctifying the new month based on the testimony of witnesses who observed the new moon. After confirming the sighting, messengers were sent out to inform Jewish communities about the new month’s beginning.. This process is described in the Mishnah, Rosh Hashanah 2:6–7:
“Initially, they would light beacons. Once the Samaritans caused confusion, they decreed that messengers should go out. How would they test the witnesses? The pair who came first would be tested first. They would bring in the elder of them and say to him: ‘Tell us how you saw the moon.'”
This eyewitness system required rapid communication of the new month’s declaration, especially crucial for holidays falling at the month’s start, like Rosh Hashanah.
The Unique Challenge of Rosh HashanahThe sighting of the new moon of Rosh Hashanah, which occurs on the first day of the 7th month (Tishre), could not be communicated in time to distant communities. As a result, it is assumed that the Sanhedrin, or at least the communities in the diaspora, instituted a two-day observance for communities outside of the immediate vicinity of Jerusalem, a practice known as yom tov sheni shel galuyot (the second festival day of the Diaspora). The Mishnah (Rosh Hashanah 4:4) notes the need for witnesses and the Beit Din to sanctify the month:
“Whether it was seen clearly or not clearly, they sanctified it. Rosh Hashanah was to be celebrated in Jerusalem alone.”
This statement indicates the complexity of determining the exact day, emphasizing why even those close to Jerusalem needed clarification on the new month.
Two Days for All of Israel
Unlike other festivals, the two-day observance of Rosh Hashanah extended to all of Israel, not just the Diaspora. The Talmudic explanation is found in Rosh Hashanah 30b:
“Since the people would go out to the court, but the court would delay the sanctification of the new moon until the following day, they established a two-day holiday even in the Land of Israel.”
This was due to the uncertainty caused by the potential delay in proclaiming the new month, which could only be resolved by eyewitness testimony, and as the decision to proclaim the new month could be delayed until the 30th day of Elul. The transition to a fixed calendar in the 4th century by Hillel II eliminated the need for eyewitnesses and messengers. Academic sources, such as Sacha Stern’s *Calendar and Community: A History of the Jewish Calendar, Second Century BCE–Tenth Century CE, argue that this shift theoretically should have resolved the issue of uncertainty:
“The Jewish calendar was reformed, and a calculated system was introduced. This change, however, did not alter the liturgical practice of two days of Rosh Hashanah, which continued as a safeguard against any future re-establishment of the observational system” (Stern, 2001, p. 106).
Medieval Halachic Codification
The observance of two days continued due to the principles of minhag avoteinu b’yadeinu (the customs of our forefathers are in our hands). This is codified in Maimonides’ Mishneh Torah, Laws of the Sanctification of the New Month 5:8:
“Even though today we calculate the months and know the precise day of Rosh Hashanah, the custom remains to observe two days, due to the possibility of the Sanhedrin being reinstituted.”
This continuation of two days ensured that communities remained uniform in observance.
Medieval Jewish communities in Eretz Yisrael, particularly under Byzantine rule, initially observed only one day of Rosh Hashanah. Historical accounts, such as those documented in the writings of Rav Ya’akov ben Asher in the Tur, Orach Chaim 600, indicate that the custom varied:
“In some places in the Land of Israel, they observe one day, but the consensus has become to observe two days everywhere, even in Eretz Yisrael.”
The influence of the Ramban (Nachmanides) and his students in the 13th century was instrumental in solidifying the two-day observance. Ramban, in his Responsa (Teshuvot HaRamban, 257), emphasized the importance of maintaining this practice universally to prevent division among communities:
“Since the matter is established from the days of the Geonim, and we have received the practice from our forefathers, even those in Eretz Yisrael should not deviate, so as not to cause division.”
Ramban’s students, upon moving to Eretz Yisrael, pushed for conformity, gradually influencing the Byzantine Jews to accept the two-day observance.
Ta-Shma in his Keneset Mehkarim argued that the insistence on two days was not only a halachic concern but also a socio-political effort to unify Jewish practice across the different regions:
“The persistence in enforcing the two-day observance reflected broader efforts to standardize Jewish ritual practices in the medieval period, responding to the fragmentation of the Jewish world” (Ta-Shma, 1992, p. 217).
Geonim and Rishonim who mention one day
During the medieval period, certain communities in Eretz Yisrael resisted the two-day observance, adhering to a one-day practice. This resistance can be seen as a return to the original practice when the Sanhedrin was still active and only one day was necessary. While the two-day observance became standard, some Geonim and Rishonim argued in favor of one day, especially in Eretz Yisrael:
Rav Saadia Gaon (882-942): Although generally supporting two days, Rav Saadia acknowledges that the original observance was one day. In his work Siddur Rav Saadia Gaon (Responsa, Sha’arei Tzedek), he implies that the two-day observance is a safeguard rather than a strict requirement.
Rav Natronai Gaon (9th century): He responded to a query from the community of Kairouan in North Africa, stating that the reason for the two days was to prevent mistakes in distant places but acknowledged that theoretically, only one day is necessary in Eretz Yisrael (Responsa, Otzar HaGeonim, Rosh Hashanah 82).
Rabbeinu Chananel (990-1053): In his commentary on the Talmud (Rosh Hashanah 30b), he notes that the practice of two days is due to custom (minhag), suggesting that it is not fundamentally required by the law.
Rif (Rabbi Isaac Alfasi, 1013-1103): Although the Rif follows the two-day practice, he explicitly quotes the Talmudic passage that acknowledges the possibility of a one-day observance if there is no doubt about the day (Rif, Rosh Hashanah 9b).
Rabbi Zerahiah HaLevi (Razah, 12th century): In his Ba’al HaMaor on the Rif, he supports the view that the practice of two days in the Diaspora was due to historical circumstances, but in Eretz Yisrael, one day would suffice if there was certainty (Ba’al HaMaor, Rosh Hashanah 1b).
Tosafot (Rosh Hashanah 18a, s.v. “Mitoch sheyesh safek”): The Tosafists acknowledge that in Eretz Yisrael, the reason for two days was less compelling due to the proximity to the Sanhedrin and the ability to ascertain the correct day.
Conclusion:
The two-day observance of Rosh Hashanah evolved from a practical need due to calendrical uncertainties and was solidified through centuries of halachic and communal development. The influence of key figures like the Ramban and his students played a crucial role in standardizing this practice, even against initial resistance. Both traditional sources and academic research highlight the dynamic nature of Jewish legal and cultural evolution, emphasizing the interplay between halacha, tradition, and historical context.
Bibliography
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