The concept of divine revelation was central to Augustine's epistemology, or theory of knowledge. The metaphor of light is instructive. In our present earthly state we are equipped with the faculty of sight. We have eyes, optic nerves, and so forth- all the equipment needed for sight. But a man with the keenest eyesight can see nothing if he is locked in a totally dark room. So just as an external source of light is needed for seeing, so an external revelation from God is needed for knowing. When Augustine speaks of revelation, he is not speaking of Biblical revelation alone. He is also concerned with "general" or "natural" revelation. Not only are the truths in Scripture dependent on God's revelation, but all truth, including scientific truth, is dependent on divine revelation. This is why Augustine encouraged students to learn as much as possible about as many things as possible. For him, all truth is God's truth, and when one encounters truth, one encounters the God whose truth it is.
R.C. Sproul, Consequences of Ideas
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