 The reasonableness of belief that God exists is a focal issue in the Philosophy of Religion. Theist traditions typically, or some would say essentially, make a foundational claim about an authoritative source, or sources, of revealed truth. What is salient includes belief or some related sort of affirmation, not just that God exists but associated content such as that this God exists, the God who is revealed thus and so (in great historical acts, in prophets, in scriptures, in wisdom handed down, etc.). The reasonableness of theism is therefore as much a matter of the reasonableness of an epistemology of revelation as it is of a metaphysics of perfect being. The question of how God may be expected to make himself known has gained prominence through recent discussion of the argument for atheism from ‘divine hiddenness’ (Schellenberg 1993; Howard-Snyder and Moser 2002). That argument holds that a loving God would make his existence clear to the non-resistant—but this claim is open to question. Perhaps God provides only ‘secret’ evidence of his existence, purposely overturning the expectations of our ‘cognitive idolatry’ in order to transform our egocentric self-reliance (Moser 2008); besides, there may be significant constraints logically inherent in the very possibility of unambiguous divine revelation to finite minds (King 2008).