Jacob ben Asher, in
Hebrew Ya'akov ben Asher, (1270-ca 1340) was an influential
Medieval rabbinic authority. He is often referred to as the Baal ha-Turim ("Master of the Turim (Pillars)"), after his main work in
halakha (Jewish law), the
Arba'ah Turim. He was the third son of the Rabbi
Asher ben Jehiel (known as the "Rosh"), a
German-born Rabbi who moved to
Spain. Besides his father, who was his principal teacher, Jacob quotes very often in the Turim his elder brother Jehiel; once his brother Judah (see Tur Orach Chaim, § 417), and once his uncle R. Chaim(ib. § 49). According to many, Jacob moved to Spain with his father and was not born there.
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