In what follows I offer a dyptich on the assurance of salvation and its relation to good works in three Christian traditions, Reformed, Lutheran, and Catholic. The Orthodox Reformed (or the Reformed scholastics in the generations after Calvin) consider the assurance of salvation in terms of the practical syllogism: crudely put, my salvation depends on God's election, but I can tell whether I am among the elect by examining my good works. The Orthodox Lutherans (Lutheran scholastics in the generations after Luther) consider die assurance of salvation in terms of fides praevisa, or (crudely) faith that God foresees, in abstraction from the further question of whether or not God also causes it. Thomas Aquinas, comparable in method and influence, considers the sort of knowledge that observation of one's merits bestows: not certainty but conjecture.y