shudder” (Jas. 2:19). As Augustine explains, “The devils confessed Christ.… They had faith but not charity; hence they were devils.”11 The Catholic tradition follows Augustine here, holding that faith is incomplete apart from charity. Protestants tend rather to emphasize that “faith” means more than just knowing the facts about God. As Calvin says, “faith consists in assurance rather than comprehension”;12 it involves personal trust and confidence. So, when the Heidelberg Catechism asks, “What is