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Epistemology is the philosophical study of knowledge, including its nature, origins, and limitations. To this end, it attempts to define and distinguish the notions of knowledge, truth and belief.
Epistemology as it pertains to religious belief deals mainly with the standards or criterion for justified religious belief. Key concepts include justification and warrant. Arguments for the justification of religious belief are involve either internalism or externalism. The internalist criterion for justification is that we must be have cognitive access to the grounds of any belief we hold. Externalism on the other hand does not require this access, but requires that one simply have some grounds for one's beliefs.