Аннотация:Basing on the principles of functional style determination the founders of the Prague Linguistic Circle substantiated the reasonableness of singling out the “church-religious functional style” within the framework of the Russian ethnic language used by the clergy and the laity of the Russian Orthodox Church in the sphere of religious commu-nication is determined. A striking feature of this style is the incorporation of the ele-ments of the Church Slavonic language as lingua sacra into it, and the degree of this incorporation in some of its sub-styles / genres (for example, in liturgical or prayerful ones) can reach up to 100%.