Eight Doctors of the Church

The Church Fathers, Early Church Fathers, Christian Fathers, or Fathers of the Church are ancient and generally influential Christian theologians, some of whom were eminent teachers and great bishops. The term is used of writers or teachers of the Church not necessarily ordained and not necessarily "saints"—Origen Adamantius and Tertullian are often considered Church Fathers but are not saints owing to their views later being deemed heretical—although most are honored as saints in the Roman Catholic Church, the Eastern Orthodox Church, Oriental Orthodoxy, the Church of the East, Anglicanism and Lutheranism, as well as other churches and groups. The era of these scholars who set the theological and scholarly foundations of Christianity largely ended by 700 AD.

While western churches regard only early teachers of Christianity as Fathers, the Orthodox Church honors as "Fathers" many saints far beyond the early centuries of church history, even to the present day.

In each of Western and Eastern Christianity, four Fathers are called the "Great Church Fathers" as follows:

In the Roman Catholic Church, they are also collectively called the "Eight Doctors of the Church" and in the Eastern Church the three of them (Basil the Great, Gregory of Nazianzus and John Chrysostom) are honored as the Three Holy Hierarchs.

The earliest Church Fathers, (within two generations of the Twelve Apostles of Christ) are usually called the Apostolic Fathers since tradition describes them as having been taught by the twelve. Important Apostolic Fathers include Clement of Rome,Ignatius of Antioch, Polycarp of Smyrna, and Papias of Hierapolis. In addition, the Didache and Shepherd of Hermas are usually placed among the writings of the Apostolic Fathers although their authors are unknown; like the works of Clement, Ignatius and Polycarp, they were first written in Koine Greek.

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