There is nothing restful about real faith. Where belief is the easy way out, a comfortable position for pious couch potatoes, faith demands an active engagement with uncertainty. “Doubt,” wrote playwright John Patrick Shanley in the introduction to his drama of that name, “requires more courage than conviction does, and more energy; because conviction is a resting place and doubt is infinite—it is a passionate exercise.” An exercise of the heart, that is, as much as of the mind—not of one against the other, but of the two interwoven, each constantly challenging and thus enriching the other.