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The Apostolic Fathers were a group of early Christian leaders and authors who lived shortly after the apostles. Their writings are typically dated between AD 80–180. Most of the Apostolic Fathers are believed to have known the apostles personally or were connected to them in some way. Polycarp is traditionally seen as a disciple of the apostle John. Clement was likely the second, third, or fourth bishop of Rome, and he may have known some of the apostles. Hermas possibly knew Clement and thus was acquainted with the church of Rome.
At the time of the Apostolic Fathers, the main heresies plaguing the church were Gnosticism and Docetism, so presenting truth to counter those theological aberrations is a major theme of the Apostolic Fathers. The Apostolic Fathers’ writings comprise First and Second Clement, the Ignatian Epistles, Polycarp’s Letter to the Philippians, the Martyrdom of Polycarp, the Letter of Barnabas (anonymous, despite the title), the Didache (Teaching of the Twelve Apostles), the Letter (or Epistle) to Diognetus, and the Shepherd of Hermas. Some scholars also include fragments of Papias’s writing and fragments from the Apology of Quadratus, an early example of apologetics. From the beginning, all of the writings of the Apostolic Fathers were esteemed by the church as important. A few books were even included in early Bibles: 1 and 2 Clement, Shepherd of Hermas, and the Epistle of Barnabas.
The Apostolic Fathers wrote in Greek and used the Septuagint, the Greek translation of the Old Testament. Included within the writing of the Apostolic Fathers are wisdom literature, hymns, apocalyptic prophecies, teachings of Jesus, instructions for early Christian leadership, parables, reflections on biblical passages, etc. Some of the epistles of the Apostolic Fathers address the same churches and areas that the apostles themselves addressed. First Clement is a letter to the church of Corinth, written to show them their errors and persuade them to change their ways. The seven letters of Ignatius are written to churches in Ephesus, Magnesia, Tralles, Rome, Philadelphia, and Smyrna; four of these places and churches also received direct communication in the New Testament.
The Apostolic Fathers’ writings contain the same genres as the New Testament. First Clement, Ignatius’ Letters, and Polycarp’s Epistle to the Philippians are epistles, or letters, to churches or individuals. The Epistle of Barnabas is an example of a general epistle. The Shepherd of Hermas is written in an apocalyptic style and also includes parables. The Letter to Diognetus is apologetic in nature. Second Clement is much like Hebrews and is the earliest example of a Christian homily outside of the New Testament. The Martyrdom of Polycarp is a martyrology and has no New Testament parallel. The Didache is typically seen as an early manual or guide for believers; it instructs them in the basics of the faith and prepares them for baptism.
The term Apostolic Fathers dates only from the latter part of the seventeenth century. Originally, the Apostolic Fathers were called “apostolic men.” Their writings show the importance of the doctrine of the Trinity in the first and second centuries, the respect that the early church had for the apostles, and the fervent love the leaders of the church had for their congregations.