This introduction to gnosis by Christoph Markschies combines clarity with a huge wealth of learning. Markschies defines the term gnosis and its relationship to 'Gnosticism', indicating why gnosis is preferable and sketches out the main problems. He then introduces sources, both those in the Church Fathers and the more recent Nag Hammadi finds. Next, Markschies provides an overview of the early forms of 'gnosis' in antiquity, Jewish and Christian (New Testament) and the early gnostics. This is followed with an outline of the main representatives and key figures of Gnosis, especially Valentinus and Marcion. Finally Markschies explains how Manichaeism was the culmination and end-point of gnosis and introduces readers to ancient communities of 'gnostics'; and finally 'gnosis' in antiquity and the present. For this new edition the text has been updated throughout, and an additional chapter provides an overview of the most recent scholarship. There is also a useful chronological table and an annotated select bibliography.