It is recorded that he had been a disciple of 'John'. 155) was a Christian bishop of Smyrna (now İzmir in Turkey). In the Eastern Orthodox Church, three of these (Basil of Caesarea, Gregory of Nazianzus and John Chrysostom) are honored as the ' Three Holy Hierarchs'. In the Catholic Church, they are collectively called the 'Eight Doctors of the Church'. In the Catholic Church tradition, there are four Fathers each who are called the 'Great Church Fathers'. Some, such as Origen and Tertullian, made major contributions to the development of later Christian theology, but certain elements of their teaching were later condemned.

The academic field of patristics, the study of the Church Fathers, has extended the scope of the term, and there is no definitive list. In traditional dogmatic theology, authors considered Church Fathers are treated as authoritative, and a somewhat restrictive definition is used. The historical period in which they worked became known as the Patristic Era and spans approximately from the late 1st to mid-8th centuries, flourishing in particular during the 4th and 5th centuries, when Christianity was in the process of establishing itself as the state church of the Roman Empire. The Church Fathers, Early Church Fathers, Christian Fathers, or Fathers of the Church were ancient and influential Christian theologians and writers who established the intellectual and doctrinal foundations of Christianity.

The Last Christian by David Gregory