Abraham ben David
Abraham ben David (c. 1125 – 27 November 1198), also known by the abbreviation RABaD (for Rabbeinu Abraham ben David) Ravad or RABaD III, was a Provençal ḥakham, an important commentator on the Talmud, Sefer Halachot of Isaac Alfasi, and Mishneh Torah of Maimonides, and is regarded as a father of Kabbalah and one of the key links in the chain of Jewish mystics.