The presented thesis deals with the holy foolishness and other expressions of sub- standard behaviour as part of hagiography. It is examined from the point of view of the so-called "singular speech-behaviour tactics" (сингулярные рече-поведенческие тактики) and based on the analysis of texts taken from the most comprehensive corpus of the hagiographic texts written in the Church Slavonic, Dimitry of Rostov's Chetii Minei. The thesis consists of the Introduction, three main chapters, Conclusion and Bibliography. The first chapter focuses on history: it describes relevant works on the Russian hagiographic literature of the 11th-17th centuries concerning the hagiographies of the holy fools, it shows the current state of search in Russia and describes the basic monuments of literature. The second part of this chapter deals with the life and work of a great Russian writer of the turn of the 17th and 18th centuries, Dimitry of Rostov (1651-1709). The second chapter is devoted to the methodological approach used in the thesis, i.e. the singular speech-behaviour tactics as understood by E.M. Vereshchagin and V.G. Kostomarov, who introduced them in the world science. Furthermore, the wider and narrower context of the research carried in this field up to date is shown. In the third chapter, the essential...