“The history of the Church is the history, first of all, of how among humanity... a new life was created and preserved, the fire of which was kindled by Christ.” Book of the Holy Sergius Mansurova (1890–1929) embodies this author’s intimate view of the essence of the history of the Church.Only until the 3rd century. brought his “Essays” to Fr. Sergius: death interrupted work on the book. But this work retains its significance as one of the first attempts in our century to “depict,” in the author’s words, “the life of the Church in accordance with how the Church itself perceives its life and as its centuries-old literature testifies to it.” The author’s principled approach to the history of the Church is concise reflected in the table (in the Introduction), which allows us to reconstruct the general course of the further review up to the 19th century. and can serve as a most valuable tool for independent study of church history.