In the book, for the first time in world science, a detailed comparison of the theological doctrines of two great contemporaries is carried out: the Rhine mystic John Eckhart of Hochheim (c. 1260-1328) and the Athos hesychast Gregory Palamas (c. 1296-1357). The comparison is carried out on a number of key positions, which include the teachings of God and divine emanations, ecstasy and language (including the name of God), as well as the methodology of God's knowledge.