Sefer ha-yashar

work by Tam

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July 22, 2026

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The Sefer ha-yashar (meaning "Book of the Righteous") is a significant legal work authored by Jacob ben Meir Tam, a prominent French Jewish scholar and commentator on the Talmud in the 12th century. This work, first published in 1811, contains explanations of 30 tractates of the Talmud and also includes responsa, which are authoritative answers to questions concerning Jewish law.1

Jacob ben Meir Tam was a grandson of the renowned Talmudic commentator Rashi and was himself a leading figure among the French tosaphists. He played a crucial role in rabbinical synods that established rules governing the relationships between Christians and Jews during a period of changing historical conditions in medieval Europe. The ordinances he helped develop addressed the resolution of disputes among Jews, reinforced the abrogation of polygamy, and clarified the legality of Jewish divorce deeds.1

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Jacob ben Meir Tam
Tam’s major legal work is Sefer ha-yashar (first published in 1811 in Vienna; “Book of the Righteous”). It contains explanations of 30 tractates of the Talmud, as well as responsa (authoritative answers to questions about Jewish law). He also wrote religious poetry, some of which was later incorporated into the…
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Tam’s major legal work is Sefer ha-yashar (first published in 1811 in Vienna; “Book of the Righteous”). It contains explanations of 30 tractates of the Talmud, as well as responsa (authoritative answers to questions about Jewish law). He also wrote religious poetry, some of which was later incorporated into the…
Read More