The church fathers were the significant leaders of the church in the first few centuries AD, living after the last of the apostles had died. Much of their writing is useful in tracing the early history of the church, looking at early church practice and early interpretation of the scriptures. Most of their writings are easily available online.

This page also describes other people who were condemned as heretics by the church, as well as some well-known Roman or Jewish secular writers and historians from the same period. For some of the fathers, there is a link to a page giving more information about their life and work.

Some of the most well known church fathers

The name of each of the fathers acts as link to a fuller description of their life and work further down the page. For some of the fathers more details are given on a page dedicated to them.

Post-apostolic Fathers

The post-apostolic fathers are those who lived during the decades immediately following the lives of the NT apostles. Many were trained into their ministries by one of the apostles.
Clement of Rome (?-100)
Hegesippus (2nd cent) - pupil of Justin Martyr
Justin Martyr (81-165)
Papias (70-155) - pupil of John
Polycarp (69-155) - pupil of John

Antiochene Fathers

These were connected in some way with the school of Antioch, which tended to use a more literal approach to the Scriptures.
Chrysostom (345-407)
Ignatius of Antioch (69-110/5) - pupil of John
Nestorius (c.381-c.451)
Theodore of Mopsuestia (c.350-428) - pupil of Chrysostom

Alexandrian School

These were connected with the school of Alexandria in Egypt, which tended to use a more allegorical approach to the Scriptures. There was great rivalry between the schools of Antioch and Alexandria.
Athanasius (296-373)
Clement of Alexandria (150-215)
Cyril of Alexandria (376-444)
Origen (185-254) - pupil of Clement of Alexandria

Eastern church - Greek speaking

Irenaeus (130-212) - pupil of Polycarp

Western church - Latin speaking

Ambrose (339-397)
Augustine (354-430) - pupil of Ambrose
Cyprian (200-258)
Hippolytus (c. 170-236)
Jerome (340-420)
Tatian (2nd century) - pupil of Justin Martyr
Tertullian (160-220)

Cappadocian Fathers

These were from the area of Cappadocia, a region in modern Turkey
Basil the Great (c.330-379)     } brothers
Gregory of Nyssa (c.335-394) }
Gregory of Nazianzus (c.329-389)

Early Popes

Gregory I, the Great (540-604)
Leo I, the Great (390-461)

Biographical details of the church fathers

Ambrose (339-397) - Bishop of Milan

Ambrose came from a noble Roman family from Trier, but was brought up in southern Gaul (France) and received a classical education in Rome for government service. He became governor of Northern Italy and was elected bishop of Milan in 374, even though he was not baptised. He was famous as a theologian, a church administrator and a politician, becoming provincial governor of Northern Italy. He took a strong hand against Arianism, leading several church synods and seeing Arianism defeated in the western church. He encouraged monasticism and asceticism, being influenced by his family.

He introduced hymn singing in the church, the Ambrosian Chant. Some of his hymns are still sung in the modern church. He had great influence on Augustine, who was instructed and baptized by Ambrose. He was the first church leader to use his office to successfully coerce a civil leader, when he insisted on Emperor Theodosius publicly repenting for a massacre in Thessalonica. Being fluent in Greek as well as Latin, he introduced the thinking of Greek Christianity into the Latin church. St. Ambrose's day, 7th December, celebrates the day he was consecrated bishop.

Five of his surviving writings are about Christian virginity and widowhood. Others are about ethics for clergy.

Athanasius (296-373) - Opponent of Arianism

Little is known about the childhood of Athanasius. He was was brought up and trained by Alexander, the bishop of Alexandria. He defined the doctrine of the trinity in the struggles against Arianism. He is considered the greatest theologian of his time, who saved the church from Arianism. He accompanied the bishop of Alexandria to the Council of Nicea in 325, when Arianism was condemned and the full deity of Jesus proclaimed. He became bishop of Alexandria himself in 328. Because of his disagreements with the emperor, he was banished five times, including by the emperor Constantine in 355 because of his intransigence against the defeated Arians. For 50 years he maintained a valiant witness to the true deity of Jesus, 'Athanasius contra mundi'. He was a great theologian with great love for Jesus.

His works include:
On the Incarnation: Explaining the doctrine of redemption, how only God can save mankind from sin, so Jesus must be divine: His basic stand against Arianism.
Against the Gentiles: A defence of Christianity against paganism
Life of Anthony: To promote monasticism
Letter to Marcellinus: Introduced personal and devotional use of the Psalms
Easter letter of 367: The earliest witness to the 27 book canon of NT

Augustine (354-430) - Bishop of Hippo

Augustine was born in north Africa. His mother, Monica, was a Christian, who prayed for his salvation. Living a life of sensual pleasure, he studied rhetoric in Carthage and became a Manichaean. He was also interested in Greek philosophy, later bringing many of these ideas into the church, (including trans-substantiation) forming the doctrines of the church of the Middle ages.

He went to Milan to study Neo-platonism, where he was influenced by Ambrose, bishop of Milan, and was converted in 386 after hearing part of the book of Romans read. (His conversion is described in detail in his Confessions). He became a priest at Hippo in 391 and later bishop of Hippo in 396. He opened the first monastery in North Africa and started writing. He died during the siege of Hippo by the Vandals.

Augustine changed the church's theology at the time then the church was changing, from a persecuted church to a state church - a new theology for a new style church. Later, Augustine taught that the Millennium had come. The Kingdom of God was the church and the church was reigning. He taught that salvation was only through the church and the sacraments, he also taught baptismal regeneration of infants apart from their faith. He justified the use of violence to bring in God's ways - the Bible and the sword (state). His theology justified the use of force and torture to bring men into the kingdom.

He was involved in three great controversies, including refuting Manichaeism, attacking and trying to eliminate Donatism and especially the Pelagian controversy (about original sin).

His numerous works include:
Confessions: His intimate spiritual autobiography
The City of God: His view of the Kingdom of God, seeing the church as the new order rising from the ruins of the Roman Empire
The Trinity

Basil the Great (c.330-379) - Bishop of Caesarea

Basil was born into a wealthy Christian family in Pontus. He was educated in Athens and became a teacher of rhetoric in Caesarea in 356. In 357, he was baptised and visited monastic communities. He then retired to a hermitage on his family estate and became a literary defender of the Christian faith. He became presbyter in 364 and in 370, bishop of Caesarea in Cappadocia. He became known as an eloquent defender of Nicean Christianity.

He is remembered for three things:
1) Communal monasticism based on love, holiness and obedience. The Rule of St. Basil is today still the basic structure of eastern monasticism
2) Introducing social concern to monastic communities and bishops, giving away his own wealth and organising charitable works, hospitals, schools and hostels
3) Defending orthodox doctrine, especially the doctrine of the Trinity.

His writings include:
De Spiritu Sancto: Defending the deity of the Holy Spirit
Adversus Eunomium: Attacking Arianism
Homilies on Psalms
Commentary on Isaiah ch 1-6

Chrysostom of Antioch (345-407) - Bishop of Constantinople

John Chrysostom was born in Antioch and brought up by his Christian mother. He was trained as a lawyer and in rhetoric in Antioch, but was baptised about 370 and became devoted to Christian asceticism. For ten years he left the city for a more rigorous monasticism in the mountains, which ruined his health. He returned to the city and became a great preacher in Antioch, emphasising the cross and ethics. He was known as 'The golden mouth' because of his brilliant expository preaching. He was made bishop of Constantinople in 398 and soon angered the emperor's wife by his attacks on sin and immorality in the church and her opulent living. In 404, he was deposed and exiled where he later died, after being briefly recalled to Constantinople. His theology was expressed primarily in his sermons, where he used a more literal and grammatical exegesis of the scriptures. Chrysostom was one of the great men of God within the official church. He bemoaned the failure of the power of God in his own and other preacher's lives, wanting a recovery of the miraculous.

Clement of Rome (?-100)

Little is known about Clement. He was a leader in the Roman church, and was martyred around 100. He was a companion of Peter and Paul, and probably knew John. He wrote a letter (1 Clement) to Corinth to correct their jealous and proud behaviour, appealing for unity - one of the earliest Christian writings, which nearly was included into the NT. He refers to the martyrdom of Peter and Paul. This letter assumes the prominent position of the church in Rome.

He wrote:
1 Clement: A letter to Corinthian church

Clement of Alexandria (c.150 - c.215)

Titus Flavius Clemens, known as Clement of Alexandria, was a Greek theologian and writer, being one of the first of the Alexandrian theological tradition. Little is known about his life, he was born into a pagan family in Athens and went to Alexandria. He later became head of the theological school there and developed it to the most prominent in the Eastern church. His thinking had a strong emphasis on the Logos, seeing that Greek philosophy was a partial revelation preparing the Greeks for Christ, in the same was as the law prepared the Hebrews for Christ. His teaching has become known as Christian Gnosticism, where faith is enough for salvation, but knowledge should be added to that faith. Origen was one of his pupils.

His works include:
Protreptikos: An exhortation to Greeks to urge their conversion
Paedagogus: An instruction in Christian conduct
Stromata: The relation of faith to philosophy

Cyprian (c.200-258) - Bishop of Carthage

Caecilius Cyprianus was a rich and cultured man of Carthage. He was a well educated and popular lecturer, who decided to disprove Christianity, which he saw as a threat to the unity of the Roman Empire. Instead of disproving Christianity, he himself was converted. He then dedicated himself to celibacy, poverty and the Bible and became bishop of Carthage within two years. He fled for safety during the persecution under Emperor Decius. He clashed with Novatian, who wanted to exclude people from the church who had showed weakness during persecution. Cyprian stood boldly during the persecution by Emperor Valerian and was executed.

He had great influence on the Western church, which was largely harmful, including introducing the doctrine of penance. He taught that unity of the church depended more on the bishops than on theology, leading to the doctrine of the papacy. He saw no possibility of salvation outside the Catholic church. He said, "He can no longer have God for his Father, who has not the church for his mother".

His works include:
On the unity of the church: To oppose Novatian, wanting lenient treatment for lapsed Christians who denied faith during persecution

Cyril of Alexandria (376-444) - Patriarch of Alexandria

His ministry was during the controversy with Nestorius, Patriarch of Constantinople, over the person of Christ. This came to a climax with the Council of Ephesus in 431. In 428, Cyril had accused Nestorius of heresy in his distinction between the human and divine natures of Christ. He pulled the Emperor and the Pope into the struggle and Nestorius was finally exiled. For political reasons he had encouraged the rivalry between Antioch and Alexandria and had condemned Nestorius, partly to extend his own influence in the church. He also encouraged one of the first attacks by the church on the Jews, when synagogues were destroyed and thousands of Jews were expelled.

Gregory I, the Great (540-604) - The first Pope (590-604)

Gregory is considered to be the first pope of the medieval period. He was born into a wealthy and pious Roman family. He inherited much wealth, which he used to establish seven monasteries, including one on his family estate in Rome, where he became a monk. In 577, he became one of the seven deacons responsible for administering the Roman church. He was elected pope in 590, after time as papal nuncio in Constantinople.

He increased the power, authority and organisation of the papacy after the fall of Rome in 476. During the absence of an emperor, he made peace agreements with the invaders and helped the Vatican become a separate political power. He believed that the Roman pope was Peter's successor, and supreme head of a universal church. He also increased the political influence of the papacy. He taught many of the standard Roman Catholic doctrines, including sacrificial nature of the Mass and the dogma of purgatory. He revised the liturgy for worship and introduced the plain chant, known as Gregorian chant.

He also had great pastoral and evangelistic concerns. He believed that the church must not forget the spiritual needs of individuals and increased the benevolent work of the church. In 596, after seeing fair haired slaves, he commissioned Augustine of Canterbury to bring the Christian faith to England. He also encourage missionary efforts among the Jews.

His famous book:
Pastoral Rule: A practical book on pastoral care

Gregory of Nazianzus (c.329-c.389)

Gregory was one of the Cappadocian Fathers. He was born into an aristocratic Christian family near Nazianzus in Pontus, where his father, Gregory, was bishop. He studied rhetoric in Athens and returned to Nazianzus to join Basil in the monastic life. He was ordained priest in his father's church and later led the Church of the Resurrection in Constantinople. He was called 'The Theologian' because of his eloquent sermons supporting the orthodox view of Christ's deity and opposing Arianism. He was significant in clarifying the theology of the Trinity and of Christ. He maintained both the unity and the distinctiveness of the three persons of the Trinity.

His writings include:
Defence of the Trinity
Orations: Five Theological orations, Defending divinity of Son and Spirit, including Oration 2, a Treatise on the priesthood
Epistle 101: A statement of orthodoxy adopted in the Councils of Ephesus and of Chalcedon.

Gregory of Nyssa (c.335-c.394)

One of the Cappadocian Fathers in the Eastern church. He was the younger brother of Basil the Great. He entered a career in rhetoric and probably married. After his wife's death, he entered Basil's monastery in Pontus, where he dedicated himself to asceticism and theological study. He became bishop of Nyssa (Turkey), but was removed by emperor Valens, who was supported by the Arians. After the death of Valens, he triumphantly returned. He vigorously defended the Nicene view at the Council of Constantinople (381).

His works addressing theological controversy include:
Against Eunomius: Refutation of Arianism
To Ablabius: Defending the doctrine of the Trinity
Catechetical Oration: Systematic treatment of Christian doctrine for instruction of young Christians
Exegetical works: The Life of Moses, homilies on Song of Songs, Ecclesiastes, Lord's Prayer and the Beatitudes, written in allegorical style
On Virginity: Christian asceticism

Hippolytus of Rome (c.170-c.236)

Hippolytus was a Greek-speaking presbyter in the church in Rome. He was exiled to Sardinia during the persecution by emperor Maximius (235), where he died as a martyr. He had a theological conflict with bishop Callistus of Rome, and was elected as rival Pope. Hippolytus made a greater distinction between the Father and the Christ, where Callistus emphasized divine unity. Hippolytus was also more rigorous on church discipline, denying reconciliation to the church of those guilty of major, especially sexual, sins.

His writings included:
Refutation of all Heresies: dealing with gnostic sects
Apostolic Tradition: The organisation and liturgy of the anti-Nicene church, including baptism, eucharist and ordination.
Commentary on Daniel: the earliest commentary from the Orthodox church

Ignatius (69-110/5)- Bishop of Antioch

Ignatius was a pupil of the apostle John, he became the bishop of Antioch in early second century and was executed in Rome in 110 or 115. The emperor Trajan, on a visit to Antioch, ordered Ignatius to be arrested. Trajan presided at the trial and ordered him to be thrown to the wild beasts at Rome. On his journey to Rome, he wrote a seven letters, including one to the Christians there begging them not to try and arrange his pardon, he longed for the honour for dying for his Lord. He urged unity in the Church, saying that there should be one bishop over each congregation to prevent splits and to correct beliefs. He condemned the Docetist ideas (Jesus being pure spirit being, only seeming to be a man). He put a high value on communion. He wrote seven works including The Glory of Martyrdom, Hatred of Heresies and The Authority of Clergy, giving us a valuable record of first century church life.

Irenaeus (130-212) - Bishop of Lyons

Irenaeus was born in Asia Minor, he studied under Papias and Polycarp (bishop of Smyrna), who had been a disciple of the apostle John. He travelled widely as a missionary and became bishop of Lyons in 177, finally being martyred at the time of Emperor Setimius Severus. Against the teaching of gnosticism, he stressed the fundamental Christian doctrines and the historical roots of the faith. He helped to develop the doctrine of apostolic succession, where secrets are passed on from the apostles to the bishops who followed them. He urged conformity with the Church at Rome, where he said that the apostolic tradition had been faithfully preserved. His writings are the earliest we have which quotes from both the OT and NT as we know it.

Jerome (340-420) - Biblical scholar and translator

Jerome's Latin name was Eusebius Hieronomous. He was born at Strido (near the modern border between Italy and Slovenia) and was raised as a pagan and educated in Rome, where he was impressed by the tombs and catacombs of the Christian martyrs. He travelled to Gaul, where he was converted and was baptised in 360. He gave up his career for an ascetic life of meditation and spiritual work. He travelled to Asia Minor and Syria, where he learnt Hebrew and Greek. He became an adviser to Pope Damascus in 382, and had a large audience among Rome's wealthy upper-class women. He finally become a monk in Bethlehem in 384, and introduced monasticism into the Latin church. He aimed to introduce the best of Greek learning to Western Christianity. He translated the Bible into Latin. This is known as The Vulgate and is still the classic Latin Bible. He also wrote many commentaries. He became a leading biblical interpreter in the Western church, recommending a threefold interpretation (historical, symbolic and spiritual) which has led to many allegorical and mystical interpretations.

He wrote:
The Vulgate: The Latin translation of the Bible.

Justin Martyr (81-165) - Christian Apologist

Justin was born in Neapolis, the ancient Shechem. He became a convert from paganism, having seen much persecution of Christians. He searched for truth in a variety of philosophical schools, seeing the Gospel as the truest and most perfect philosophy. He was finally led to the Lord by an old man. He continued to visit the philosophical schools now sharing his faith. He taught in Ephesus and Rome, become a famous Christian apologist, defending the Christian faith. He also effectively battled against gnosticism. He was martyred in Rome and awarded the name "Martyr".

This is Justin Martyr's description of early Christian worship:"On Sunday a meeting is held of all who live in the cities and villages, and a section is read from the Memoirs of the Apostles and the writings of the prophets, as long as time permits. When the reading is finished, the president, in a discourse, gives the admonition and exhortation to imitate these noble things. After this we all arise and offer a common prayer. At the close of the prayer, bread and wine and thanks for them according to his ability, and the congregation answers "Amen". Then the consecrated elements are distributed to each one and partaken of, and are carried by the deacons to the houses of the absent. The wealthy and the willing then give contributions according to their freewill, and this collection is deposited with the president, who supplies orphans, widows, prisoners, strangers and all who are in want."

His books include:
First apology: To Emperor Antoninius Pius against claims that Christians were atheistic and immoral.
Second apology: A protest to Emperor Marcus Aurelius against the injustice of Christians being executed.
Dialogue with Trypho: A debate with Trypho, a cultured Jew, who said that Christians broke the Jewish law and worshipped a man.

Leo I, the Great (390-461) - Pope (440-461)

He led the Western Church at the very end of the domination by the Roman empire in the west. Taking advantage of the weakness of the Roman Empire, he greatly increased the power of the papacy, at the start of the medieval period. He was highly gifted as a mediator, which he used to persuade Attila and the Huns to stop the seige of Rome and unsuccessfully to avert an attack on Rome by the Vandals. After the fall of the city, he led the people in restoring government and bringing relief to the devastated city.

He was a great administrator, who sought to control all of Christendom, particularly areas devastated by barbarian invasions. He assumed the old imperial title of 'Pontifex Maximus'. He was the first bishop of Rome to use Mt 16:18-19 to justify his position as 'papa' of the church. He placed the claims of papal supremacy into a highly structured legal setting. His vision was of a highly hierarchical church with everything converging on Rome and with Rome as the centre of the Holy Roman Empire.

Nestorius (c.381-c.451)

Nestorius was born in Syria and became patriarch of Constantinople in 428. He probably studied under Theodore of Mopsuestia and became a fierce opponent of Arianism. He distinguished two natures in Jesus Christ, the human Jesus and the divine Word of God. He also attacked the use of the popular title of the Virgin Mary, the God-bearer, or mother of God (theotokos). His greatest opponent and rival was Cyril of Alexandria. Nestorius was condemned as a heretic by the Pope in 430 and Cyril pronounced 12 anathemas against him. In 431 the General Council at Ephesus deposed Nestorius and sent him back to a monastery in Antioch. Five years later he was banished to Upper Egypt. His followers formed the Nestorian church, which spread over a vast area of Persia, India and as far as China.

His writing includes:
Book of Heracleides: His apology, justifying his position and answering Cyril's criticisms

Origen (185-254)

Origen was the greatest scholar and most prolific author of the early Greek church. He quoted two-thirds of the NT in his writings. He was born to a Christian family in Alexandria, where he experienced the Holy Spirit in childhood. After his father's death during a persecution he took over teaching new converts in and later, more advanced students in the renowned school in Alexandria. He lived a very ascetic life and was opposed by the bishop of Alexandria who forced him to move to Caesarea. He even castrated himself, taking Mt 19:12 literally, so he could teach female students. He died from torture wounds from the persecution under emperor Decius.

He taught that there were three basic levels of meaning in any biblical text: literal sense, moral application to the soul and the allegorical (spiritual) sense. He used much of the Platonic philosophical ideas of his time in his theology, which led him to condemned as a heretic by the church in the 6th century. He distinguished the true (spiritual) church, those who had personally experienced the power of the Gospel in their lives, from the institutional church.

His books include:
Hexapla: A parallel edition of the OT, with Hebrew OT, Greek transliteration, three Greek translations and the Septuagint.
First Principles: A systematic presentation of fundamental Christian doctrines in terms of Greek thinking: God, Christ, Holy Spirit, creation, the soul, free will, salvation and the authority and inspiration of the scriptures.
Against Celsus: Against pagan criticism of Christianity.
Exhortation to Martyrdom and Prayer

Papias (70-155) - Bishop of Hierapolis

Papias was a pupil of the apostle John, he became bishop of Hierapolis. He may have known Philip, who probably died in Hierapolis. He was martyred in Pergamum about the same time as his friend Polycarp. He was one of the earliest writers in the Church.

He wrote one book, now lost, but portions are quoted in writings by Eusebius:
Explanation of the Lord's discourses: He inquired of the elders to have the exact words of Jesus.

Polycarp (69-155) - Bishop of Smyrna

Polycarp was instructed by the apostle John. He became the greatly loved bishop of Smyrna for 40 years and was martyred in his old age in 155, one of the last to have known any of the apostles. He was revered for the quality of his godly life and gentle manner. He wrote a letter to the Philippians and taught Irenaeus. His martyrdom during the persecution under Marcus Aurelius is described in a letter - The Martyrdom of Polycarp. He was brought before the governor and offered his freedom if he would curse Christ. He replied, "For 86 years I have served Christ and He has done me nothing but good, how then could I curse him, my Lord and Saviour?" He was burned alive.

Tatian (2nd cent) - Christian apologist

Tatian was born in Assyria. He was a pupil of Justin Martyr in Rome and one of the many great thinkers who became Christians and then wrote apologies (literary defences of the Christian faith) dedicated to the emperor, and read by the educated public, to answer accusations against Christianity and to point out the intellectual weaknesses of paganism. Later in life, Tatian travelled to the East and became severely ascetic, rejecting all physical matter and acts as evil. He was denounced as a heretic in 173.

His only writing:
Diatesseron: A harmony of the four gospels, used by the Syrian church

Tertullian (160-220)

Quintus Septimus Florens Tertullianus, known as Tertullian, lived most of his life in Carthage. He was a son of a pagan Roman government official and became a Roman lawyer. He studied in Rome, where he was converted in 197 after being impressed at the courage of Christian martyrs. He was the first major Christian author to write in Latin, introducing many of the common theological terms. He is remembered as the father of Latin Christianity. He was the first person to use the term 'Trinity'. He is known for his pithy sayings, like, "The blood of the Christians is the seed of the church". He had strict moral views which led him to join the severe ascetic Montanists in 207, being disenchanted with the lax worldliness of the priests of the Roman church. He gives us the first reference to infant baptism, in 197, when he condemns the practice. He also opposed the growing distinction between clergy and laity.

His books include:
Apology: Addressed to Roman magistrates, arguing for toleration of Christianity, that Christians should have equal treatment in law
Against Marcion: Use of the OT by the church, oneness of God
Against Praxeas: Doctrine of trinity and nature of Christ
Exclusion of heretics: Claimed scriptures as exclusive property of the church, against the Gnostics.
On the Soul: The first Christian writing on psychology
On Baptism: The earliest work on baptism, criticising infant baptism

Theodore of Mopsuestia (c.350-428)

Theodore was a leader in church in Antioch and became bishop of Mopseustia, east of Tarsus (392- 428). He was a great commentator of the scriptures, using a more historical approach, typical of the Antiochene school, in contrast to Origen's more allegorical approach. He opposed Arianism and attended the Council of Constantinople in 394. He was a friend and follower of John Chrysostom. He later taught Nestorius. Both doubted whether it was right to describe Mary as the 'God bearer'. Because of some of his Pelagian thinking, he was condemned as a heretic in 553, after his death.

Famous heretics and opponents of Christianity

Defining who is a heretic is difficult. Some teachers in the early church were without doubt heretics, whose teaching was certainly not orthodox. There were also many who were condemned as heretics, later to be re-admitted to the church, often after their death. Some leaders became more un-orthodox later in their lives. Others were condemned as heretics because of political or personal disagreements with other bishops. Often in reality, a teacher is seen as heretical by one group and a great leader by an opposing point of view, which may or may not be right.

Some of the people described as early church fathers above were condemned as heretics. Others taught views which today would be seen as incorrect or harmful.

Arius (c.290-c.335)

Arius was a north African priest, probably born in Libya. Arianism, which was one of the most troublesome divisions in the church was named after him. He became a deacon in Alexandria and by 318 came into conflict with the bishop of Alexandria over the nature of Christ. Arius had great personal devotion to Jesus, but in his teaching, he downgraded Christ to a position where he was not quite God and not quite man. He denied that Jesus was one with the Father. Arius clashed with bishop Alexander of Alexandria and was condemned in the synod of Antioch. The emperor Constantine intervened and called the council of Nicea in 325. This council condemned Arius and his teaching. The Nicene Creed was written against the teaching of Arianism. Arius was banished to Illyricum, but still continued to write and teach. Athanasius became the strongest opponent of Arianism. The argument continued for many years after Arius' death, with Constantine later being involved on the side of Arius. Arianism essentially denied the deity of Jesus. The Jehovah's Witnesses are essentially a modern manifestation of Arianism.

Celsus (180)

A famous literary opponent of Christianity. He covered almost every idea, so that all modern arguments were already found in his writings.

Cerinthus (c.50-100)

Cerinthus was a Gnostic teacher and opponent of the apostle John in Ephesus. Irenaeus wrote about his heretical views in book 1 of his Against Heresies. His views included the denial of the virgin birth, and that the Christ came on Jesus like a dove at his baptism and departed before the crucifixion, because the Christ could not suffer. This view is also found in the Koran. He basically separated the Jesus from the Christ (Messiah). He was possibly connected with the Nicolaitans (Rev 2), as he is traditionally associated with immorality. According to Irenaeus, when John entered the bath house and found Cerinthus there, he rushed out without bathing, exclaiming, "Let us fly, lest the bath house fall down because Cerinthus, the enemy of the truth, is within".

Marcion (c.85-c.160)

The infamous heretic, Marcion, was born in Sinope in Pontus, the son of a bishop. He went to Rome in 144, studied under a gnostic teacher. He rejected all the OT and the NT except Luke and ten of Paul's letters, after which he was excommunicated. The Marcionites had their own rival churches, clergy and rituals. His churches were strictly ascetic, forbidding marriage. They finally disappeared by the fourth century. Tertullian wrote "Against Marcion" and described him as a foe of true doctrine. Justin Martyr said that Marcion was aided by the devil to blaspheme.

He distinguished between the creator and redeemer Gods, saying that judgement belongs to the creator God and redemption to the Father, the unknown God before the coming of Christ. His teaching speeded up the formation of the orthodox canon, creed and organisation of the church. The teaching had similarities to the gnostics. The Old Testament was the revelation of the creator God, God of the Jews, who was a lesser, evil and self-contradictory god. Jesus was not the Messiah of the OT, but a revelation of the God of love, the redeemer God, and who appeared to suffer on the cross. He said that the original twelve disciples were too Jewish, and so Paul was sent to restore the true gospel.

He wrote:
Antithesis: Showing contradictions between the two testaments. It replaced the book of Acts in the Marcionite Bible

Pelagius (?-c.419)

Pelagius was a monk from Wales. He arrived in Rome around 400, teaching what was to become the heretical teaching of Pelagianism. He had a high view of human nature, which effectively denied the need for God's grace and the doctrine of original sin. He taught that Adam was a mortal man, who would have died whether he had sinned or not. Pelagius insisted that any man could live a sin-free life if he tried hard enough.

He travelled to North Africa in an attempt to meet Augustine. Although they never met, Augustine became violently opposed to Pelagius's teaching, insisting that original sin came through Adam to every person, and that only God's grace can save us. Pelagianism was condemned by a series of synods from 412 to 418. Pelagius was banished from Rome in 418 and probably died in the East before 420.

Porphyry (233-300)

Porphyry was a Greek Neo-platonist philosopher, born in Tyre or Syria. He settled in Rome in 262, becoming a disciple of Plotinus. He was a powerful influence against Christianity.

Valentinus (100–c.160)

Valentinus was the most famous gnostic teacher. He taught in Alexandria and came to Rome in 140. He had many followers and wrote several books, including: The Gospel according to Philip, The Gospel of Truth and possibly the Letter of Rheginos. He taught that man's lostness was due to ignorance.

Other significant writers and historians (Jewish, Greek and Roman)

Eusebius (263-339) - Famous church historian

Eusebius was born in Palestine, and saw many martyrdoms in Egypt and was imprisoned himself during the persecution under Emperor Diocletian. He became bishop of Caesarea at the time of Constantine's conversion (313/4). He became a close friend and admirer of Emperor Constantine and a keen follower of Origen. He helped to create the Christian empire of Byzantium, being a typical court bishop of the fourth century. He was the first person to write a exhaustive history of the first three centuries of church, from Christ to the council of Nicea. He supported the banishment of Athanasius during the early part of the Arian dispute. Later, at the Council of Nicea he joined in condemning Arianism.

He wrote:
Ecclesiastical History: History of first centuries of the church
Chronicles: To justify Christianity against paganism

Hegesippus (110–180)

Hegesippus was a historian, who was the first to work out lists of apostolic succession. These were lists of bishops, starting from the apostles, which guaranteed an unbroken handing down of the apostle's doctrine. This was to counter the Gnostics who appealed to a succession of teachers traced back to the apostles.

Herodotus (484-424 BC) - Greek historian

A widely travelled Greek historian, especially known as writer of history of the struggle between Greece and Persia and the defeat of the attempted Persian invasion of Greece in 490 and 480 BC.

He wrote:
History of Herodotus

Josephus (37-100) - The famous Jewish historian.

Flavius Josephus was born into a priestly Jewish family, he became a Pharisee at the age of 19. In the Jewish revolt against Rome (66-70), he commanded the Jewish force in Galilee until he was captured by the Romans in 67. After his capture, he helped the Romans and went to Rome with Titus. He became a close friend of the emperor Vespasian and his son Titus, taking the emperor's family name, Flavius. He was officially freed and returned to Jerusalem in an attempt to convince the Jews holding the city to surrender to the Romans.

His books include:
Jewish wars: About the Fall of Jerusalem in AD 70
Antiquities of the Jews: History of the Jews from creation
Against Apion: Defence against pagans, to commend Judaism to Romans

Philo (c.20 BC - AD 45) - The famous Jewish philosopher

Philo was a member of a rich and influential Jewish family from Alexandria, he spent much of his life in the duties of public service, spending his spare time in a life of contemplation and Hellenistic philosophical writing. In AD 40, he undertook a mission to Caligula to protest at the emperor's claim to divine honours. Using allegorical exegesis, he extracted moral and mystical teaching from the scriptures. His desire was to demonstrate that the philosophical and religious searchings of the Gentile world found their true goal in the God of Abraham. He was influenced by the Stoic, Pythagorean and Platonist thinking. He used philosophy to provide a rationale of religion, making himself the first theologian. His concept of the "Logos", from Stoic thought, described the way that a transcendent God created and sustained the world and revealed himself to men. This concept probably influenced the apostle John.

His books included:
The allegory of the laws: A commentary on Genesis
The exposition of the laws: A review of the history of the Pentateuch

Pliny the elder (23-79)

Gaius Plinius Secundus, was born in northern Italy, he held political and military posts in the Roman empire and was killed in the eruption of Vesuvius. He wrote a "Natural History" dealing with astronomy, geography, zoology and mineralogy.

Pliny the younger (61-113)

Gaius Plinius Caecilius Secundus, the nephew of Pliny the elder was governor of Bithynia from 111 to 113. His correspondence has great historical interest.

Suetonius (2nd century) - Roman historian

Gaius Suetonius Tranquillus was a Roman historian. In his writing he mentions the expulsion of the Jews from Rome by Claudius.

He wrote:
Lives of the Twelve Caesars

Tacitus (c.55-120) - Roman historian

Cornelius Tacitus was an eminent lawyer. He married the daughter of Julius Agricola and was a consul under Emperor Nerva in 97. In his description of the fire of Rome, he gives a vivid description of Nero's persecution of the Christians, followers of Christ, who was put to death by the procurator Pontius Pilate. He says that this dangerous superstition, was suppressed for a while, then broke out again, not only in Judea, but even in the city (Rome), and were charged with setting the city on fire.

He wrote:
Annales :History of the Empire from Tiberius to Nero
Historiae: History of the Empire from Galba to Domitian (69-97)
Germania: Description of the German tribes

Information from:
WA Elwell. Evangelical Dictionary of Theology
HH Halley. Bible Handbook
EH Broadbent. The Pilgrim Church
DJ Theron. Evidence of Tradition
WP Barker. Who's Who in Church History