The name of Georgios Moschabar is not particularly known to the general public and this is because his activity was mainly behind the scenes in a time of intense political and ecclesiastical developments for Byzantium. The sources of the time testify little about the antitheon theologian, while the older and modern studies of his life and activity are isolated and, as it turns out, incomplete. This was also the reason I chose to deal with the personality of Georgios Moschabar, in order to illuminate all aspects of his activity and to highlight his work and the impact it had during the 13th century. as well as later. (...) (FROM THE FOREWORD OF THE PUBLICATION)