With this book, Father Dimitrios Bathrellos attempts to outline the dogmatic theology of the Orthodox Church based on the writings of Saint Simeon of Thessaloniki (+1429), who has been aptly described as "the John of Damascus of the 15th century".

At the same time, the book constitutes the first international study of the dogmatic teaching of Saint Simeon of Thessaloniki. By analyzing and commenting on this teaching, Father Dimitrios presents on the one hand a summary of the orthodox doctrinal tradition as it crystallized at the end of the Byzantine period, and on the other hand the contributions of Saint Simeon himself to this tradition. In addition, the author attempts to utilize this tradition with the aim of the most successful possible formation of our doctrinal theology and its testimony in the field of modern theological thought.