He is best known for his multi-volume gnosticism series, including Gnostic Return in Modernity and Gnostic Apocalypse: Jacob Boehme's Haunted Narrative. Rehabilitating a project attempted in the nineteenth century by a leader of the Tübingen school of theology, Ferdinand Christian Baur, O'Regan attempts to identify a gnostic structure or "grammar" that can be traced through sources and authors as diverse as Valentinianism and William Blake.
Christian | Hans Christian Andersen | Christian Dior | Ferdinand Marcos | Ferdinand Magellan | Christian music | Franz Ferdinand | Christian cross | Christian Brothers | Ferdinand II of Aragon | Congregation of Christian Brothers | Christian IV of Denmark | Franz Ferdinand (band) | Contemporary Christian music | Christian Slater | Archduke Franz Ferdinand of Austria | Christian rock | Ferdinand von Mueller | Ferdinand I, Holy Roman Emperor | Ferdinand I | Christian metal | Christian Broadcasting Network | The Christian Science Monitor | Southern Christian Leadership Conference | Institute of the Brothers of the Christian Schools | Ferdinand | Christian Church | Union of Christian and Centre Democrats | Louis-Ferdinand Céline | Ferdinand Foch |