Isaac ben Abba Mari was a 12th-century French rabbi often referred to as “Ba’al HaIttur,” (“Author of the Ittur”) for his magnum opus, Sefer HaIttur. From a family of notable rabbinic scholars, Isaac began writing legal works at the age of seventeen. In addition to his impactful Sefer HaIttur, he also wrote comments on Rabbi Isaac Alfasi’s Sefer Halakhot, entitled Meah Shearim.