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Q&A Wednesday: Saadiah Gaon and the calendar, with Nadia Vidro

T-S 8Ka10.2
T-S 8Ka10.2 f. 3v: Saadiah's work Kitāb al-Tamyīz is mentioned in the last line of this fragment.
Melonie Schmierer-Lee and Nadia Vidro
Wed 22 Sep 2021

Nadia, you’re starting a new project today. Can you tell us about it?

This new project, entitled “Saadya Gaon’s works on the Jewish calendar: Near Eastern sources and transmission to the West”, is a collaboration between UCL, London and LMU, Munich, and is funded by the Fritz Thyssen Foundation. The project is led by Professors Sacha Stern and Ronny Vollandt, with me as the research associate.

Saadiah b. Joseph al-Fayyūmī, better known as Saadiah Gaon (882–942 CE), was the most important and influential scholar of Judaeo-Arabic culture in the 10th century. The head of the rabbinic academy of Sura, a polemicist and a polymath, Saadiah produced a vast body of writings that had a lasting impact on Jewish literature and culture. His works cover philosophy, liturgy, grammar, Bible translation and exegesis, religious law, and other areas of intellectual activity. Yet Saadiah’s literary production on the calendar and his role in the development of the Jewish calendar literature have not received much scholarly attention. Saadiah composed at least four works on the calendar and the calendar polemics, and possibly some others that are attributed to him in 10th-century Jewish and Muslim sources but appear lost. It is our aim to reconstruct, edit, and study, for the first time, the full surviving corpus of Saadiah’s writings on the Jewish calendar.

Why was calendar so important to Saadiah?

In the first half of the 10th century, the Jewish calendar had become a major issue for Near Eastern Jewish communities. A calendar controversy broke out in 921/2 CE between the Rabbanite communities in Babylonia and Palestine. Alternatives to the Rabbanite calculated calendar were practiced by various Jewish factions including the Karaites and the Tiflisites, and groups such as the Mishawaites were uncertain how the calendar should be fixed. The intensity of 10th-century calendar debates was an outcome of the major changes that had occurred through the 9th century, with the institution of a new calendar based on calculation which was widely followed by the Rabbanites by the beginning of the 10th century. These debates were not just about the technical question of how to set the months and years. The calendar structured all aspects of social and economic activity, defined the rhythms of religious liturgy and worship, and provided a focus for communal and religious identities. Conflicts over calendar were fights for legitimacy, authority, and legal independence. It is therefore hardly surprising that the calendar was of great interest to Saadiah Gaon, a preeminent scholar and communal leader of rabbinic Babylonian Jewry in the first half of the 10th century.

What was Saadiah’s position on the calendar?

Perhaps, the best known of Saadiah’s calendrical views is his controversial (and historically inaccurate) theory of the origins of the Jewish calendar. According to this theory, the fixed calculated calendar practiced by medieval Rabbanites was primeval and given to Moses on Mount Sinai. Saadiah substantiated his claims with biblical proofs, arguing, for example, that Noah must have calculated the calendar during the Flood, when the skies were covered (Genesis 7:10–8:4), that the Israelites in the wilderness could not have seen the moon as they were led by a pillar of cloud by day and a pillar of fire by night (Exodus 13:21–22), and that David and Jonathan knew in advance when it would be the new month (1 Samuel 20:18). This polemical claim contributed to Saadiah’s general argument for the Oral Tradition and to his theory that revelation was the sole source of rabbinic Jewish law. It was also very important in Saadiah’s polemic against the Karaites, who believed that originally the Jewish calendar was set by observation of natural phenomena.

Did Saadiah’s works on the calendar have any lasting consequences for medieval Judaism?

Saadiah’s claims on the prophetic origins of the Jewish calendar had a significant impact on later scholarship. They were widely debated in the Jewish East and West, by preeminent Babylonian geonim like Hai Gaon (d. 1038) and by Rabbanite authorities in al-Andalus. Saadiah’s claims elicited an especially strong polemical response from the Karaites, who followed a calendar based on observation. Karaite calendar texts from the 10th century onwards focus strongly on disproving Saadiah’s theory and unpicking his supporting evidence; the refutation of Saadiah’s claims and arguments is, indeed, foundational for Karaite calendar writing. Most Rabbanite authorities also rejected Saadiah’s theory and argued that it was only intended as a polemic against the Karaites; but the theory was taken up to some extent a thousand years later by some 20th-century Haredi ideologists. The theory thus still has resonances in Judaism today.

In addition, Saadiah authored one of the earliest extensive treatises on the principles of the Rabbanite calendar calculation, Kitāb al-Tamyīz. This work is usually defined in secondary literature as polemical, but our preliminary analysis shows it to be in first place a didactic treatise on the principles of the calculated Rabbanite calendar. Composed about one hundred years after the calendar calculation was instituted in its present-day form in the Near East, this treatise appears to have been an important vehicle for the transmission of the Rabbanite Jewish calendar theory to the West. His work gave an impetus to the development of calendar monographs as an important branch of Jewish literature, that became valued both in its own right and due to its close connections with mathematics, astronomy, and religious law.

Is the famous calendar controversy of 921/2 CE part of the project?

The calendar controversy of 921/2 CE was a major controversy between the Jewish communities of Palestine and of Babylonia, about the dates of the Jewish festivals. For two years, these communities observed Passover, Rosh Hashanah and all other festivals on different dates. To fight out the disagreement and to secure the allegiance of Jews within the orbit of their authority, Palestinians and Babylonians wrote numerous polemical letters as well as a memorandum for future generations (traditionally but erroneously known as Sefer ha-Moʿadim). It is traditionally believed that Saadiah Gaon was one of the major if not the most important player on the side of the Babylonians. Recently Sacha Stern edited and studied anew all surviving documents of the calendar controversy and came to the conclusion that Saadiah’s role in it was limited (The Jewish Calendar Controversy of 921/2 CE). This conclusion has been contested by some scholars who believe that the memorandum, one of the most important documents of the controversy, was composed by Saadiah Gaon. The study of Saadiah’s whole corpus of writings on the calendar, in this new project, will help to either confirm or disprove Stern’s argument. 

Is the Genizah our main source for Saadiah’s writings?

All currently known manuscripts of Saadiah’s works on the calendar are preserved in the Cairo Genizah collections around the world, and in the Firkovich collection in the Russian National Library in St. Petersburg. All these manuscripts are fragmentary, with folios of the same manuscripts sometimes scattered in different libraries world-wide. It is almost certain that the Genizah has more fragments of Saadiah’s works on calendar, which are waiting to be identified.

Do you think any autographs have been preserved?

At present there are no identified Saadiah autographs, though there is a reference in one Genizah fragment to an autograph of Saadiah's commentary on some book of the Bible, written on parchment. That autograph may or may not have been preserved in the Genizah. Trying to identify that manuscript would be our best chance to perhaps find a Saadiah autograph, but nobody’s done the work so far. There are no such leads (known to me) about the calendar corpus.

Thanks for your time, Nadia!

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