LEVI, known also as RALBAG (1288-1344), Jewish philosopher and commentator, was born at Bagnols in Languedoc, probably in 1288. His family had been distinguished for piety and exegetical skill, but though he was known in the Jewish community by com mentaries on certain books of the Bible, he never seems to have accepted any rabbinical post. Possibly the freedom of his opinions may have put obstacles in the way of his preferment. He was at Avignon and Orange during his life, and is believed to have died in 1344, though Zacuto asserts that he died at Perpignan in 1370. Part of his writings are commentaries on Aristotle, or rather of commentaries on the commentaries of Averroes. Some of these are printed in the early Latin editions of Aristotle's works. His most important treatise, that by which he has a place in the history of philosophy, is entitled Milhamoth 'Adonai (The Wars of God), and occupied 12 years in composition (1317-29). A portion of it, containing an elaborate survey of astronomy as known to the Arabs, was translated into Latin in 1342 at the request of Clement VI.
The Milhamoth is throughout modelled after the great work of Jewish philosophy, the Morek Nebuhim of Moses Maimonides, and may be regarded as an elaborate criticism from the more philo sophical point of view (mainly Averroistic) of the syncretism of Aristotelianism and Jewish orthodoxy as presented in that work. Gersonides was also the author of a commentary on the Penta teuch and other exegetical and scientific works.