The Sethians were one of the main currents of Gnosticism during the 2nd and 3rd century AD, along with Valentinianism and the Basilidians. According to John D. Turner, it originated in the 2nd century
Seth. Patriarchs line in iconostasis. Zhdan Dementiev, Vologda. Cathedral of the Assumption, St. Cyril-Belozersky Monastery. Museum of Cyril Belozersky Monastery.