The Ba'al Shem Tov is an elusive subject for historians because documentary evidence about his life is scanty and equivocal. Until now, much of what was known about him was based on stories compiled more than a generation after his death, many of which serve more to mythologize him than to describe him. The portrait Moshe Rosman provides is drawn from life instead of from myth. Based on innovative critical analysis of familiar and previously unexplored...