Rabbi Gottlieb effectively combines profile and theology in this accessible and enlightening biography of Rabbi Yehudah Leib Ashlag (1885–1954), a master of the kabbalah, who is widely-credited with opening the study of kabbalistic texts to ordinary people. Gottlieb, a student of Ashlag’s son, opens in 1892, with a legend about the rabbi, then a seven-year-old child in Warsaw and himself the son of a Hasidic rabbi; according to the story, Ashlag was lying in bed when he was struck in the head by a book that fell from a shelf. His father told him that the volume, a book of kabbalah, was meant only for angels, but the precocious child insisted, “ ‘If it has been printed, it must be meant for everyone.’ ” Gottlieb goes on to trace his subject’s life, including his rabbinic ordination and marriage, prodigious scholarly output, his immigration to what became the nation of Israel in 1921, and production of the essential kabbalist textbook Talmud Eser Sefirot. Lay readers may be most interested in the religious figure’s teachings, which include such messages as, “Each of us needs to learn that the whole purpose of our spiritual work is to come to love our fellow.” Gottlieb’s glowing work preserves the life and legacy of a significant, if now obscure, religious thinker. (Self-published)