Isaac ben Sheshet

Isaac ben Sheshet Perfet (1326 – 1408) (Hebrew: יצחק בן ששת) was a Spanish Talmudic authority, also known by his acronym, Rivash (ריב"ש). He was born at Valencia and settled early in life at Barcelona, where he studied under Perez ha-Kohen, under Hasdai Crescas, and especially under R. Nissim ben Reuben (RaN), for whom he professed throughout his life the greatest veneration.

Although Isaac acquired while still young a world-wide reputation as a Talmudic authority, and halakic inquiries were addressed to him from all quarters, he led a private life, earning his livelihood in commerce until he was about fifty years old, when he was compelled to accept a position as rabbi. Together with six other prominent men of Barcelona, among whom was his younger brother Judah ben Sheshet and his teacher Nissim ben Reuben, he was thrown into prison on a false accusation. After his acquittal he accepted the rabbinate of Zaragoza; but troubles still awaited him. To the grief caused by the death of his brother Judah and of his son-in-law was added that due to dissensions in the community, stirred up by the dayyan Joseph ben David. Isaac in consequence accepted the less important rabbinate of Calatayud; but when he was on the point of leaving Zaragoza the leaders of that community induced him to stay. The peace, however, did not remain long undisturbed, and Isaac settled at Valencia, where he directed a Talmudical school.

In 1391 occurred the great persecutions of the Jews of Spain in consequence of the preaching of Fernandes Martinez. Isaac saved himself by flight. After sojourning a certain time at Miliana he settled at Algiers, where he was received with great honor. Fate, however, had decided that he should not find peace.

A certain Spanish refugee who had settled at Algiers before him aspired to become the leader of the community, and, seeing in Isaac a rival, began to persecute him. To give to Isaac the power necessary to act against this man, Saul ha-Kohen Astrue persuaded the government to appoint Isaac rabbi of Algiers. But this won for him a still more powerful enemy in the person of Simeon ben Zemah Duran (Rashbaz), who disapproved of any intervention on the part of the government in the affairs of the rabbinate.

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