Long before Prozac … David (right) strikes up a pleasant tune on the harp, trying to lighten Saul’s mood after the king is stricken by “a bad spirit from Yahweh” (1 Samuel 16:14), in this 1657 painting by Rembrandt van Rijn. The artist depicts Saul with the characteristic distant, brooding look of melancholia—a favorite theme of artists in the Renaissance. These days, Saul’s recurring moodiness would probably earn a psychiatric diagnosis like bipolar disorder; and drugs, not music, would be the doctor’s prescription. But the Hebrew Bible had a very different explanation of human misfortune: sin. Demons or spirits such as the one that periodically afflicted Saul were a direct result of violating the covenant with God. Ironically—or fortuitously—Saul’s possession by this spirit is what first brings his already-anointed successor David into contact with him, marking the beginning of Saul’s eventual downfall.