The author’s earlier linguistic and textual analysis of collections containing readings on particularly revered memorable dates and the lives of the most revered saints revealed the manuscript Festal Menaion and Chrysostom from the collection of Tikhonravov No. 185 (from the collection of the Russian State Library) as containing unique information about the Church Slavonic language of the 15th century. This time, as traditionally considered, is a clear indicator of the second South Slavic influence, but evidence of this influence (according to the collection) was not in the Word on the Council of the archangel Michael and Gabriel, the author of which was Clement of Ohrid. There were obvious colloquial elements, but the colloquial (common) facts of the Russian language are especially clearly recorded in another monument of this collection – in the Torment of Paraskeva Friday. In this article, this text is analyzed in comparison with the texts presented in the Great Menaion Reader of the SVT. St. Demetrius of Rostov and in the collection of the 15th century from the Collection of the Trinity Lavra of St. Sergius.
 The author defines the broad and narrow contexts of the study. The first is connected with the Church Slavonic problems (language, writing), the second with the 15th century, the time when the so-called ‘second South Slavic influence’ was fully manifested. Church Slavonic itself is not a scientific term, although it emerged from a scientific tradition. We can define what the Russian language is by referring to ethnic and geographical boundaries, cultural and spiritual traditions, historical certainty, and keeping in mind, which is very important for the language, its ‘functional side’. It is impossible to evaluate the Church Slavonic language from these positions. Russian is a language that has developed different principles of development, and in relation to the Russian language, the Church Slavonic language appears to be as much an independent unit (a separate scientific ‘subject’) as the dialect language, which was the subject of lively discussions in its time, or the Russian spoken language, which occupies a strong position in the niche of the Russian language to this day.
 The Church Slavonic language is ultimately the desired object of Slavistic research, and the way to determine its structure and functional status lies through the analysis of specific written sources. The conclusions about the ‘colloquial’ (‘simple’, perhaps common) Church Slavonic language of the Torment of Paraskeva Friday according to the list of Thn-185 are quite obvious, the language of the monument according to this list destroys the myth of the so-called ‘second South Slavic influence’.
 The analysis allows us to take a new look at what we call the Church Slavonic language, to understand that the Church Slavonic language is still an unidentified linguistic object, rather than a philological one, because this language cannot be separated from the text. The text is the environment in which it exists. Linguistics has adopted the tools of linguistic analysis, which since ancient times served philological purposes, it is already presented in the ΤνΝη γραμματική of Dionysius of Thrace, but it did not serve to describe and understand language as such, the main task of grammatics was considered to be the evaluation of the work, “what is the best of all that grammar does”. This helps in the qualification of what is written in the Church Slavonic language: it should not only contain the traditional forms and vocabulary of this language (also with the traditional permissibility of innovations), but also have a functional correlation, correspond to the sphere of existence of Church Slavonic texts.