In a traditional society, religious skepticism results in intellectual and behavioral anarchy, unless the standard method of doubting is followed. In this article, through providing an interpretation of Cartesian rules for doubting customary beliefs, I present a set of rules as the principles that must be followed in revisiting religious beliefs. After a short review of the roots of religious skepticism, I discuss the destructive impact of personal predispositions on one’s religious judgement. Then, through elaboration of logical structure of a belief system, I elucidate how fundamental doubts epistemologically differ from the rest. Next, I argue that how theoretical and behavioral skepticisms are different and how important it is to demarcate these two, when we doubt our religious beliefs. Finally, I discuss the ethic of religious skepticism and social responsibilities of religious intellectuals.