Abstract
<jats:p>The research aims to identify trends in the development of the Church Slavonic language within the Old Believer milieu during the 19th and 20th centuries. The article examines excerpts from the “Revelation of St. John the Divine” and their interpretations, which reflect the general eschatological focus of the Old Believers and were used as separate chapters or works within moral-didactic miscellanies. The scientific novelty of the study lies in the fact that graphic, orthographic, and lexical variants of Apocalypse excerpts and their commentaries are described for the first time based on Old Believer manuscript collections from the first quarter of the 19th century, the second half of the 19th century, and the early 20th century, held in the funds of the “Art Culture of the Russian North” museum association. The study establishes that the Apocalypse verses and their interpretations cited in the manuscripts hold different compositional significance depending on the purpose of the collection. Discrepancies with traditional source texts were noted, raising the question of a common prototype for copying these miscellanies. The identified variations in the texts indicate a gradual alignment with modern Church Slavonic norms.</jats:p>