The course of Patrology II, taking for granted the themes of Patrology I, will focus on the study of Patrology between IV and V. The starting point will be the Council of Nicaea, with the political, doctrinal and social developments that characterize it and with the subsequent developments of the Aryan crisis characterizing the fourth century. Attention will then focus on the concept of Neonicenism and how the Council of Constantinople is an expression of this new hermeneutic of the Council of Nicaea. As part of the study of the Trinitarian question, the beginnings of the Christological question will be studied, which will find a synthesis, only partially resolving, in the Council of Chalcedon. The study of the development of Christian thought will be conducted through the presentation of the life and works of the fathers, paying particular attention to their doctrinal contribution.