In this paper, I am outlining a new, and perhaps controversial, account of Locke's epistemology. I argue that the common denominator in any act of assent in both the natural and religious epistemologies is the regulating role of reason. Key to the regulating role of reason is the requirement that any cognitive achievement, whether of knowledge, probability, or matter of faith, meets epistemic conditions at different stages or from different points of view. By employing the same justificatory structure throughout his epistemology, Locke offers a way in which reason can be seen to go as far as it can to justify itself (its reliability as well as its scope) from within its own natural limitations.