(ca. 1180–ca. 1250), legal scholar. Usually referred to as Yitsḥak Or Zaru‘a from the title of his main work, Yitsḥak ben Mosheh was born in Bohemia. He studied in Prague with Yitsḥak ben Ya‘akov ha-Lavan, the latter’s son Ya‘akov ben Yitsḥak, and Avraham ben ‘Azri’el (the “Old Man of Bohemia”).
Although he did not have an easy life in his youth and was often destitute, Yitsḥak ben Mosheh traveled extensively to centers of the Ashkenazic Diaspora, studying with such scholars as Yehudah he-Ḥasid in Regensburg, Eli‘ezer ben Yo’el in Bonn, El‘azar ben Yehudah in Worms, and Simḥah ben Shemu’el in Speyer. In France, where he lived in about 1215, Yitsḥak was a student of Ya‘akov ben Me’ir and Shim‘on ben Shimshon of Coucy. Yitsḥak then served as a rabbinic judge and directed a school in Würzburg, where one of his students was Me’ir ben Barukh of Rothenburg, a later authority of Ashkenazic Jews. He ultimately settled in Vienna, where he spent the rest of his life as a teacher and scholar.
Yitsḥak ben Mosheh’s major work is the halakhic compendium Or zaru‘a. Although the text remained in manuscript for centuries (it was published gradually in four volumes, in 1862 [Zhitomir] and 1887–1890 [Jerusalem]), it was highly regarded throughout the Middle Ages. In addition to the author’s own opinions, Or zaru‘a contains commentaries and responsa by scholars with whom Yitsḥak was in contact either in person or through correspondence. Covering topics found in Talmudic tractates, the work provides a picture of the legal status of Jews in Central Europe and of the spiritual and material life of its communities. Passages refer to Prague (Praga, or Prag) and to Bohemia (Czekhakh, or Pihem), often mentioning the Land of Canaan, a term generally used by medieval Jewish scholars to describe the Slavic regions.
Another important element in Orzaru‘a is the large number of Old Slavonic and Old Czech glosses in what the author calls “our language, the language of Canaan.” These glosses, which explain difficult Hebrew expressions, are an important and hitherto underestimated source for the history of the Czech language (‘Arugat ha-bosem, a liturgical commentary by Avraham ben ‘Azri’el [ca. 1234], is of similar importance). From the structure of the compendium, it is clear that Yitsḥak composed it over many years, and also that appendixes by his students and his son Ḥayim Eli‘ezer were added after his death. The large scope of the work made it difficult to copy exactly, which was why Ḥayim Eli‘ezer compiled an abridged version (Simane or zaru‘a, printed in 1862; Ḥayim Eli‘ezer’s own reesponsa were published in 1865). An extract from Or zaru‘a was later also copied by Yitsḥak ben Ḥayim, Yitsḥak ben Mosheh’s grandson, and quotations and references from the entire work appear in a number of texts by subsequent authors of halakhic literature.
Isaak Markon, “Die slawischen Glossen bei Isaak Or Sarua,” Monatsschrift für die Geschichte und Wissenschaft des Judentums 49 (1905): 707–721; Vladimír Sadek, “Medieval Jewish Scholars in Prague,” Review of the Society for the History of Czechoslovak Jews 5 (1992–1993): 135–149; Chaim Tykocinski, “Lebenszeit und Heimat des Isaak Or Sarua,” Monatsschrift für die Geschichte und Wissenschaft des Judentums 55 (1911): 478–500; Efraim Elimelech Urbach, Ba‘ale ha-tosafot (Jerusalem, 1986).
Translated from Czech by Stephen Hattersley