This book demonstrates that ancient Christian Gnosticism was an ancient form of cultural criticism in a mythological garb. It establishes that, much like modern forms of critical theory, ancient Gnosticism was set on deconstructing mainstream discourses and cultural premises. Strains of critical theory dealt with include the Frankfurt School, queer theory, and poststructural philosophy. The book documents how in both ancient Gnosticism and modern critical theories issues that used to serve as premises for discussion or as concepts relegated to the realms of the "natural" and the "given" in their respective historical contexts, are transformed into objects of contention. The main aim of this book is to salvage the historical category of Gnosticism from its present scholarly disavowal, if only because Gnosticism, when read as a cultural, and not only a religious phenomenon, presents us an ancient form of culture criticism which would be hard to parallel until (post) modernity. While Hans Jonas remarked many years ago that "something in Gnosticism knocks at the door of our Being and of our twentieth-century Being in particular," by the 21st century global world this something has already entered and lives with us. We can thus still benefit from another perspective, even if it comes from Mediterranean people who lived almost 2,000 years ago.

Building on critical work in biblical studies, which shows how a historically-bounded heretical tradition called Gnosticism was 'invented', this work focuses on the following stage in which it was "essentialised" into a sui generis, universal category of religion. At the same time, it shows how Gnosticism became a religious self-identifier, with a number of sizable contemporary groups identifying as Gnostics today, drawing on the same discourses. This book provides a history of this problematic category, and its relationship with scholarly and popular discourse on religion in the twentieth century. It uses a critical-historical method to show how and why Gnosis, Gnostic and Gnosticism were taken up by specific groups and individuals - practitioners and scholars - at different times. It shows how ideas about Gnosticism developed in late nineteenth- and twentieth-century scholarship, drawing from continental phenomenology, Jungian psychology and post-Holocaust theology, to be constructed as a perennial religious current based on special knowledge of the divine in a corrupt world. David G. Robertson challenges how scholars interact with the category Gnosticism, and contributes to our understanding of the complex relationship between primary sources, academics and practitioners in category formation.