"Nomocanon at the Great Trebnik" is a collection of church rules, published from 1658 at the end of the Great Trebnik under the title "Nomocanon, sirech the Lawgiver, having rules, by reduction, of the holy Apostle, the Great Basil and the holy cathedrals." Initially, it existed as a separate book, which served as a guide for confessors in making confession and imposing penances on penitents. In 1872, Professor Alexei Stepanovich Pavlov published Nomocanon under the Great Trebnik, published together with a Greek original, still unknown, and with an explanation by the publisher. This edition included a Greek original, previously unknown, and contained explanations and critical notes by the author. In 1897, Pavlov produced a revised and expanded edition entitled Nomocanon under the Great Trebnik: Its History and Texts, Greek and Slavic, with explanatory and critical notes. In this work, he explored in detail the history and texts of Nomocanon, providing a scientific solution to issues that arose in the last century in the Holy Governing Synod. Pavlov noted that the Nomocanon was based on a penitentiary attributed to Patriarch John of Constantinople Postnik, with his reduced terms of penances. He claimed that the Nomocanon was a new edition of Postnikov's Nomocanon adapted for its time.