The book, which is the result of many years of work by the author on texts from Nag Hammadi and other ancient written sources, comprehensively investigated various aspects of that religious phenomenon of the first centuries AD. e., which in the science of modern times is called "Gnosticism." The author offers his view on the nature of this phenomenon as a whole, simultaneously considering many particular issues of the existence of Gnostic texts. The book gives a Coptic text and a commented translation of one of the most interesting Gnostic texts - "The Apocalypse of Peter."