Al-Mursid Al-Kafi

Tanhum Hayerushalmi composed his 'Sufficient Guide' - the only lexicon ever composed to the Mishne Tora of Maimonides - in order to explain the difficult Hebrew words in the text to readers of Judaeo-Arabic. Aiming to give each Hebrew term a precise definition in Arabic, he examined its root and brought a quotation to show its use in context. In the entries, which are arranged alphabetically, the author compares the halakhic terms with expressions drawn from the Bible and its translations into Aramaic and Arabic, categorizes them, and sometimes points out their etymological connections. The sources for his explanations include the writings of Judah Hayyuj and Jonah ibn Janah, the Arukh of Nathan ben Yehiel, and Maimondes' Arabic commentary on the Mishna. All these elements make the Lexicon of great importance to research on the history of the Hebrew language in the Middle Ages in general, and to the study of Hebrew lexicography in particular.