Joseph Karo, expelled from Spain as a child, was a rabbi, talmudist, mystic, and preemiment halakhic codifier. His best-known work, the Shulchan Arukh, was accepted in his lifetime and formally recognized thereafter as the definitive statement of Jewish legal and religious practice. He also wrote basic commentaries on Rambam's Mishneh Torah and Jacob ben Ashe's Arba'ah Turim, both of which were major sources for his own Shulchan Arukh. As a mystic, he also received heavenly revelations. Some of these were set down in writing and contributed to his decision to migrate to the land of Israel. There, he lived in Safed, where he supported the effort of his teacher, Rabbi Yaakov Berav, to revive traditional rabbinic ordination (Hebrew: semikhah).