The creations of Deacon Fyodor - the spiritual son of Archpriest Avvakum, fellow prisoners and compassion of his great mentor - represent one of the most important pages in the history of early Old Believer theology, being both an expression of mature rejection of Nikon's reform and the beginning of polemics within the part of the Russian church that did not accept the reform. The book includes all the famous works of Deacon Fedor. The book is intended for a wide range of readers interested in medieval Russian literature, the history of Russia and the Russian church.