The article deals with the introduction of new technical devices by Russian religious poet Stanislav Krasovitsky, which connects the tradition of zaum in the avant-garde with the search for a new mystery. As a pioneer of religious poetry during the Thaw period, Krasovitsky anticipated the mystery turn in Soviet culture: the use in rock operas, films and animations of the mystery plot as capable of uniting the various symbols of world culture. For Krasovitsky, the main technical device is the introduction of new letters into the Russian alphabet, taken from Greek and Latin, which allow conveying visual impressions through an unusual combination of sounds and creating a special atmosphere of mystery. It is shown that this project by Krasovitsky is closely related to the development of semiotics and cybernetics and the understanding of scripts as implementing programmed pragmatics in special operational symbols. Krasovitsky did not engage in poetic production for more than two decades, preferring religious asceticism, but at the same time he developed a theoretical justification for his turn from the avant-garde to mystery along the lines of the acts of the Baroque era. He constructed a consistent historiosophy in which paganism, the cult of Apollo, and Christianity were the three stages in the acquisition of truth, and each stage corresponded to its signs, letters, and symbols, containing both semantics and iconically marked pragmatics. This allowed Krasovitsky to combine reflections on the nature of letters with reflections on ritual, and to create late poetry already simply as legitimizing his own priestly rituals. This study allows us to clarify the peculiarities of perception of religious and philosophical issues in the culture of the Soviet period and show how formal experiments, including those supported by a specific medium of typewriter, allowed a new arrangement of verbal and visual elements in the work.