12th century Tosafist, renowned for his Halakhic and ethical work on the 613 commandments, "Sefer Yerei'im". His Tosafot to Talmud are mentioned by later authorities but are no longer extant. He was a prime student of Rabeinu Tam and teacher of Ra'avyah and R' Elazar, author of "Rokeach."
Works on Sefaria
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