The early church fathers fall into three basic categories: apostolic fathers, ante-Nicene church fathers, and post-Nicene church fathers. The apostolic church fathers were the ones like Clement of Rome who were contemporaries of the apostles and were probably taught by them, carrying on the tradition and teaching of the apostles themselves. Linus, mentioned in 2 Timothy 4:21, became the bishop of Rome, and Clement took over from Linus. Both Linus and Clement of Rome, therefore, are considered apostolic fathers. However, there appear to be no writings of Linus that have survived, while many of the writings of Clement of Rome survived. The apostolic fathers would have largely passed from the scene by the beginning of the second century, except for those few who might have been disciples of John, such as Polycarp. The tradition is that the apostle John died in Ephesus around A.D. 98.
The ante-Nicene fathers were those who came after the apostolic fathers and before the Council of Nicea in A.D. 325. Such individuals as Irenaeus, Ignatius, and Justin Martyr are ante-Nicene fathers.
The post-Nicene church fathers are those who came after the Council of Nicea in A.D. 325. These are such noted men as Augustine, bishop of Hippo, who is often called the father of the [Roman Catholic] Church because of his great work in Church doctrine; Chrysostom, called the “golden-mouthed” for his excellent oratorical skills; and Eusebius, who wrote a history of the church from the birth of Jesus to A.D. 324, one year before the Council of Nicea. He is included in the post-Nicene era since he did not write his history until after the Council of Nicea was held. Other post-Nicene fathers were Jerome, who translated the Greek New Testament into the Latin Vulgate, and Ambrose, who was largely responsible for Augustine’s conversion to Christianity.
So, what did the early church fathers believe? The apostolic fathers were very concerned about the proclamation of the gospel being just as the apostles themselves proclaimed it. They were not interested in formulating theological doctrine, for the gospel they had learned from the apostles was quite sufficient for them. The apostolic fathers were as zealous as the apostles themselves in rooting out and exposing any false doctrine that cropped up in the early church. The orthodoxy of the message was preserved by the apostolic fathers' desire to stay true to the gospel taught to them by the apostles.
The ante-Nicene fathers also tried to stay true to the gospel, but they had an additional worry. Now there were several spurious writings claiming to have the same weight as the established writings of Paul, Peter, and Luke. The reason for these spurious documents was evident. If the body of Christ could be persuaded to receive a false document, then error would creep into the church. So the ante-Nicene fathers spent a lot of their time defending the Christian faith from false doctrine, and this led to the beginnings of the formation of accepted church doctrine.
The post-Nicene fathers carried out the mission of defending the gospel against all kinds of heresies, so more and more the post-Nicene fathers grew interested in methods of defending the gospel and less interested in transmitting the gospel in a true and pure form. Thus, they began to slowly fall away from the orthodoxy that was the hallmark of the apostolic fathers. This was the age of the theologian and endless discussions on secondary topics.
The early church fathers are an example to us of what it means to follow Christ and defend the truth. None of the early church fathers were perfect, just as none of us are perfect. Some of the early church fathers held beliefs that most Christians today consider to be incorrect. What eventually developed into Roman Catholic theology had its roots in the writings of the post-Nicene fathers. While we can gain knowledge and insight by studying the early church fathers, ultimately our faith must be in the Word of God, not in the writings of early Christian leaders. Only God’s Word is the infallible guide for faith and practice.