This book by Prof. A.P. Lebedev is a logical continuation of his work on the history of the Byzantine Church in the 6th–7th centuries. Following the same plan as in the previous book, the author aims to illuminate the religious life of Byzantine society over four centuries. This was a very difficult period in the history of Byzantium. On the one hand, there is a decline in its political significance and level of state life, and on the other hand, there is a period of rise of Byzantine culture and education (the so-called “Comnenian” and “Palaeologian” revival). A.P. Lebedev examines the internal life of the Byzantine Church in all its aspects - the relationship between the Church and the state in theory and practice, the moral state of society in a given period, the state of Byzantine education, the material and moral position of the clergy. Vivid characteristics of the emperors and patriarchs of Constantinople significantly enliven the study. This work, like all the works of A. P. Lebedev, has a solid scientific basis in the form of Russian and foreign research, and is based on a serious analysis of various sources. It is written in a lively scientific language and will be of interest both to specialists in the history of Byzantium and the Byzantine Church, and to a wide range of readers. The publication is equipped with indexes and the latest literature on the subject of research.