In the judgment of some scholars, the Gospel of Thomas contains material as old as anything in the canonical Gospels. For a representative treatment, see Stevan Davies, The Gospel of Thomas and Christian Wisdom (New York; Seabury, 1983). For the story of the discovery and significance of the Nag Hammadi documents, see especially John Dart, The Jesus of Heresy and History (San Francisco; Harper & Row, 1988). In Biblical Archaeology Review, see James Brashler, “Nag Hammadi Codices Shed New Light on Early Christian History,” BAR 10:01.