This book traces the historical lineages of Alvin Plantinga's religious epistemology from Plato through Augustine and Calvin. It focuses upon this epistemology as a philosophical interpretation of what is generally taken to be a narrow theological doctrine. The author provides a textually based and closely reasoned introduction to the epistemological ideas of Plato, Augustine, Calvin, Plantinga, and several other writers and shows the continuity of a certain approach to the knowledge of God; it may be called the Platonic--Augustinian--Reformed (or Calvinist) approach.