The writings ascribed to the Athenian convert of St. Paul, Denys (or Dionysius) the Areopagite, made their first appearance the early sixth century. Since then, through the Renaissance and beyond, they have exercised an enormous influence on Christian thought, both in the East and in the West. Yet who their author was remains in soluble mystery. This book explores Denys' theology, which draws both on the great Greek theologians of the fourth century - the Cappadocian Fathers - and on the stridently pagan philosophical tradition of late Athenian Neoplationism, as well as showing affinities with the Christian thought of Syria. In this comprehensive introduction, Andrew Louth explores Denys' theology, presenting a compelling vision of the beauty of God's revelation, joined with a profound awareness of the ultimate mystery of the unknowable God.