Rabbi Shimon ben Zemach Duran (1361-1444) was a colorful rabbinic authority in Algiers. In his book, Zohar Harakia, on methods of enumerating the 613 commandments, he summarizes the work of previous authorities on this subject, especially Maimonides and Nachmanides. He also presents his own system of enumeration. Thus, his work is a compact introduction to this fundamental subject. The text, first printed in 1515, is written clearly and arranged as...