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 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. In traditional dogmatic theology, authors considered Church Fathers are treated as authoritative, and a somewhat restrictive definition is used. The academic field of patristics, the study of the Church Fathers, has extended the scope of the term, and there is no definitive list. 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. Great Fathers In the Catholic Church and Eastern Orthodox Church traditions there are four Fathers each who are called the "Great Church Fathers". In the Catholic Church, they are collectively called the "Eight Doctors of the Church", Western Church • Ambrose (A.D. 340–397) • Jerome (347–420) • Augustine of Hippo (354–430) • Pope Gregory I (540–604) Eastern Church • Athanasius of Alexandria (c. 296 or 298 – 373) • Gregory of Nazianzus (329 – c. 390) • Basil of Caesarea (c. 330 – 379) • John Chrysostom (347–407) In the Eastern Orthodox Church, three of them (Basil of Caesarea, Gregory of Nazianzus and John Chrysostom) are honored as the "Three Holy Hierarchs". Apostolic Fathers The Apostolic Fathers were Christian theologians who lived in the 1st and 2nd centuries AD, who are believed to have personally known some of the Twelve Apostles, or to have been significantly influenced by them. Their writings, though popular in Early Christianity, were ultimately not included in the canon of the New Testament once it reached its final form. Many of the writings derive from the same time period and geographical location as other works of early Christian literature that did come to be part of the New Testament, and some of the writings found among the Apostolic Fathers' seem to have been just as highly regarded as some of the writings that became the New Testament. The first three, Clement, Ignatius, Polycarp, and Papias of Hierapolis are considered the chief ones. Greek Fathers Those who wrote in Greek are called the Greek (Church) Fathers. In addition to the Apostolic Fathers, famous Greek Fathers include: Justin Martyr, Irenaeus of Lyons, Clement of Alexandria, Athanasius of Alexandria, John Chrysostom, Cyril of Alexandria, the Cappadocian Fathers (Basil of Caesarea, Gregory Nazianzus, Gregory of Nyssa), Peter of Sebaste, Maximus the Confessor, John of Damascus and Origen of Alexandria. Latin Fathers Those fathers who wrote in Latin are called the Latin (Church) Fathers. Tertullian, Cyprian of Carthage, Hilary of Poitiers, Ambrose of Milan, Pope Damasus I Jerome of Stridonium, Augustine of Hippo, Pope Gregory the Great and Isidore of Seville. Syriac Fathers A few Church Fathers wrote in Syriac; many of their works were also widely translated into Latin and Greek such as : Aphrahat, Ephrem the Syrian, Isaac of Antioch and Isaac of Nineveh. Desert Fathers The Desert Fathers were early monastics living in the Egyptian desert. Although they did not write as much as other Church Fathers, their influence was also great, and they are credited with beginning the practice of monasticism, and codifying many of its features. Among them are Paul of Thebes, Anthony the Great and Pachomius. Many of their, usually short, sayings are collected in the Apophthegmata Patrum ("Sayings of the Desert Fathers"). Patristics The study of the Church Fathers is known as patristics. Works of fathers in early Christianity, prior to Nicene Christianity, were translated into English in a 19th-century collection Ante-Nicene Fathers. Those of the First Council of Nicaea and continuing through the Second Council of Nicea (787) are collected in Nicene and Post-Nicene Fathers. Tradition Byzantine Byzantine Tradition التقليد البيزنطي βυζαντινή παράδοση Византийская традиция Tradición Bizantina Tradizione Bizantina מסורת ביזנטית Byzantinische Tradition बीजान्टिन परंपरा بازنطینی روایت