Aaron ben Meïr

Aaron HaKohen ben Meïr was a rabbi and a Nasi (head of the Sanhedrin) of the Palestinian Gaonate in the first half of the tenth century. His name was brought to light by several fragments discovered in various genizoth (the store-room or depository in a synagogue (or cemetery), usually specifically for worn-out Hebrew-language books that were stored before they could receive a proper cemetery burial). The fragments contain an account of a controversy between Ben Meïr and the Talmudic Academies in Babylonia regarding the Hebrew calendar.

Introducing a new rule in the fixation of the molad (lunar conjunction) of the month of Tishri, Ben Meïr in 921 CE decreed that, in the year 922, Passover and the other Jewish feasts should be celebrated two days before the date prescribed by the traditional calendar. The sage and scholar Saadia Gaon, who was at that time staying at Baghdad, objected, along with the Babylonian academies. Ben Meïr, however, refused to yield to their injunctions, denying them any authority in astronomical matters; and, owing to his own reputation and that of his family, won the confidence of Jews in many countries.

A letter from the exilarch David ben Zakkai and the Babylonian notables was sent to ben Meïr, imploring him not to cause a schism and showing him the fallacy of his calculations with regard to the calendar. Ben Meïr answered in an arrogant fashion, and was then excommunicated by David ben Zakkai and the academies. Circular letters were also sent to various parts of the world, warning the Jews against Ben Meïr's teachings. In this manner an end was made of this agitation.

According to Isaac Broydé in his Jewish Encyclopedia article about Ben Meir, the aim pursued by Ben Meïr in this agitation is obvious. He conceived the project of transferring the dignity of the exilarch from Babylonia back to the Land of Israel, and he endeavored to deprive the exilarchate of one of its most important prerogatives, which was the calculation of the calendar. The moment chosen by ben Meïr was very propitious. The exilarch David ben Zakkai had no authority, being neither a learned man nor a very scrupulous one; and of the two academies at Sura and Pumbedita, the former had no head, and the latter was directed by the ambitious Cohen Zedek.

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