The Acts of the Apostles names only two of the Athenians whom Paul won over when he spoke before the Areopagus, the city's ancient council: a woman called Damaris, and Dionysius, himself a member of the council. Around 500 a Christian writer whose real name is lost took that Dionysius as his own, and history knows him as Pseudo-Dionysius the Areopagite. Under the borrowed name he wrote four treatises and ten letters. The treatises are addressed to Timothy, Paul's companion, the letters to Titus, to John the Evangelist and to other figures of the apostolic age; in one letter he recalls watching an eclipse of the sun from Heliopolis, in Egypt, at the hour of the Crucifixion. His teaching is credited with founding negative theology: God lies beyond everything that can be said or thought, and the mind comes nearest to God when it lets go of every idea it has of him.
The writings credit their teaching to Scripture and to a revered teacher, Hierotheus, and never name a pagan philosopher, but the debt is plain: Proclus, head of the pagan Platonist school at Athens until his death in 485, had described all things flowing out from a first principle beyond being and being drawn back to it, rank by rank. The image of ascent had a Christian forerunner: Gregory of Nyssa, the fourth-century bishop and theologian, had read Moses's climb into the dark cloud on Sinai as the soul's approach to a God no eye can see; The Mystical Theology makes that climb the pattern for all knowledge of God. Scripture calls God Good, Light, Being, Life and One, and The Divine Names reads each as a name for what God gives rather than for what God is. Then the names are denied, from the crudest upward, and at last the denials themselves, until the mind is left in agnosia, an unknowing that Dionysius counts as the highest knowledge.
That pattern of ranks orders everything below God. Dionysius called it hierarchia, a sacred order: a chain in which each rank receives divine light from the one above and passes it to the one below. The angels form nine such ranks in three groups of three. The church mirrors them on earth in its bishops, priests and deacons, and in rites that bring the light to people not yet able to take it in directly. Dante followed this order in his Paradiso.
For about a thousand years most readers took the author at his word. At talks in Constantinople in 532 Hypatius, bishop of Ephesus, disputed that the writings were genuine; Maximus the Confessor, the seventh-century monk and theologian, defended them. In the West, Hilduin, abbot of Saint-Denis near Paris, had the writings put into Latin around 838 and identified their author with the abbey's patron, Saint Denis, the martyred first bishop of Paris. The doubt returned in 1457, when Lorenzo Valla, the Italian scholar, argued that the works could not be by Paul's convert. In 1895 two scholars, Hugo Koch and Josef Stiglmayr, showed independently that a chapter of The Divine Names follows a treatise on evil by Proclus. Historians now place the author around 500, probably in Syria; the first writer known to cite him is Severus, patriarch of Antioch, between 518 and 528. Of the many men proposed as the real author, from Peter the Iberian, a fifth-century bishop near Gaza, to Damascius, the last head of the Platonist school at Athens, none has won general agreement.
Read as the work of Paul's own disciple, the writings carried great weight through the Middle Ages. John Scotus Eriugena, the Irish scholar, translated them afresh in 862. Thomas Aquinas wrote a commentary on The Divine Names and cites Dionysius well over a thousand times. The unknowing passed to Meister Eckhart, to the anonymous English author of The Cloud of Unknowing and to John of the Cross. In fourteenth-century Byzantium both Gregory Palamas, the monk and theologian, and his opponents cited him. Luther judged him more Platonist than Christian.