Biography
Rabbi Isaac ben Jacob ha-Lavan was a Rishon. He appears in halachic literature in the context of the laws of Yom Tov, where his views are brought alongside other early authorities in discussions found in the Tur on Orach Chaim.
One such passage concerns the treatment of a body awaiting burial that falls on the first day of Yom Tov, weighing whether and how it may be attended to, with the opinions of Rashi, the Behag, and the Rosh set out in the surrounding discussion. His inclusion in these debates places him among the early authorities whose rulings shaped the practical halachah on this subject.
Where traditions differ. The supplied passage centers on other authorities (Rashi, Behag, Rosh); the specific position attributed to Isaac ben Jacob ha-Lavan is not clearly preserved in the excerpt.
רבינו יצחק "הלבן" בן יעקב מבוהמיה, היה אחד מבעלי התוספות במאה ה-12, מתלמידי רבנו תם והריב"א משפיירא.
Rabbi Isaac ben Jacob or Yitzhak ben Yaakov, nicknamed "ha-Lavan" or "the white" was a 12th-century rabbi of Bohemia. He was a Tosafist and liturgical poet who flourished at Prague in the late 12th century.
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