The article is devoted to comparativist research of Hesychasm phenomenon in its relations with Gnosticism. According to contemporary investigations, Hesychasm is regarded not only as Eastern Orthodox practice of silent pray, but as a broad late-byzantine intellectual movement, which was represented by Gregory Palamas and his followers such as John Cantacusenus and и Nicholas Cabasilas. This movement consists of secular form, which described as Political Hesychasm and Laical Hesychasm. Hesychast doctrine based on ideas of eternal divine energies and of Tabor Light. It means denying early-Christian an early-byzantine concepts influenced by Gnostic dualism of principles Heaven and Earth with anti-somatic position. Common place of Gnostic position is ontological pessimism as denying fallen reality, which was corrupted by sin. In this relation, Hesychasm follows Eastern Orthodox tradition, but it has other positions, which can be described as ontological optimism. Empiric material reality is not only the world of sin, but it is a space full of invisible divine energies such as Tabor Light from synoptic Gospels.