This introduction to Gnosis by Christoph Markschies combines great clarity with immense learning. In his Introduction, Markschies defines the term Gnosis and its relationship to 'Gnosticism', indicating why Gnosis is preferable and sketches out the main problems. He then treats the sources, both those in the church fathers and heresiologists, and the more recent Nag Hammadi finds. He goes on to discuss early forms of 'Gnosis' in antiquity, Jewish and Christian (New Testament) and the early Gnostics; the main representatives of Gnosis, especially Valentinus and Marcion; Manichaeism as the culmination and end-point of Gnosis; ancient communities of 'Gnostics'; and finally 'Gnosis' in antiquity and the present.There is a useful chronological table and an excellent select bibliography.