Heresies in the early church

The Christian church began with Jesus (see Church history begins). It spread due in large part to Paul (see Paul’s missionary journeys) who travelled widely to talk about Jesus. Inevitably some people became confused, or misunderstood the message. Others tried to change it for their own purposes. As a result, there were several heresies in the early church. During this time, Paul wrote several letters to groups he had visited, and some whom he hoped to visit in future. Some of the letters addressed particular problems. Some of them were general responses to queries about lifestyle for Christians. A few were personal letters to individuals. Others explained what Paul believed, why Jesus died, and what people should do to become his followers.

During this period many people decided to follow the ‘Way’ of Jesus. But others – particularly some of the ruling authorities – saw this new way of life as a threat. They tried to stop Paul and others talking about their beliefs, but that didn’t make any difference. So eventually many of the early Christians were imprisoned and put to death. You can read about some of the early Christian martyrs on the page about persecution in the early church.

Despite the death of many Jews and Christians, many of Paul’s letters survived and were passed around from group to group. The four books which we know as the Gospels – Matthew, Mark, Luke and John – were also written. They give four different perspectives on the life of Jesus. Increasingly, the church worldwide began to rely on these writings as the people who actually knew Jesus when he walked on earth became fewer and fewer.

Heresies in the early church

There were lots of people from very diverse backgrounds who became Christians. Although many were Jewish by upbringing, there were also many Gentiles, some of whom worshipped Greek or Roman gods rather than the real God. Some of them were very intelligent thinkers, and since there was no widespread Christian literature or media, there were many interpretations of the faith. Some of them were a lot further away from sound doctrine than others. Those beliefs which threatened the core of Christian faith were known as ‘heresies’.


Gnosticism was one of the mose widespread and worrying heresies in the early church, and there were several branches of it. The basic idea is a negative attitude to the material world, and the idea that salvation comes from escaping from the physical world, and receiving ‘gnosis‘ – special knowledge or revelation.

Some Gnostics are Christians; part of Christian faith is believing that Heaven awaits us, and that the things of the world are less important. In a moderate form, gnosticism is a useful antidote to rampant materialism.However, in general it is taken much further. Usually, gnosticism deniesCreation – the idea that the world was made by God and is basically good.It also denies the incarnation (that God took a human body in Jesus), which is crucial in Christian understanding. Some forms of Gnostic doctrine even say that Jesus didn’t have a body like ours – this is known as docetism. It also denies the resurrection of the body, believing that only the soul is immortal.


Another serious heresy was that of Marcion. In common with gnosticism, Marcion denied that God created the world. He also believed that the God of the Old Testament was inferior to Jesus’ Father. Marcion claimed that Yahweh, the God of the Old Testament, was cruel; whereas the true God is loving and forgiving. A Marcionite church was founded, which didn’t consider the Old Testament (the Jewish Scriptures) to be inspired, but instead used other books.

The Canon of New Testament Scripture

Some of those who believed heresies suggested certain letters and documents which should be considered sound doctrine. In response to this, a council of church leaders decided to come up with their own ‘official’ list of books and letters. That led eventually to the forming or canonisation of the 27 books which we know of as the New Testament. The four Gospels and Paul’s letters had been used widely in worship and teaching since they were first written, being copied and sent from church to church.

Apostles’ Creed and Apostolic Succession

In Rome, around the same time, an official confession of faith was determined – which we know as the Apostles’ Creed. Its aim was to state succinctly what Christians believed, and to reject the teachings of the Gnostics and Marcion.

It was also claimed that the true church showed unbroken links from the leaders back to the Apostles who were with Jesus on earth – and thus was likely to have sound teaching. This is the basis of what we call Apostolic succession. As the church grew, and became more organised, there was more clearly defined doctrine and practice, although heresies in one form or another have persisted through the centuries, and Christians still cannot always agree on sound doctrine.

Writers in the late second century

As well as the official canonisation of Scripture and the Creed, there were several documents written around this period, at the end of the second century, to reinforce and encourage sound Christian doctrine.  Some of these have survived even to today.

For instance, one of them about whom we know very little is Irenaeus of Smyrna who lived in France. He was a pastor, and his main aim in writing was to strengthen his people.

Then there was Tertullian who lived in Carthage (North Africa). He was born to pagan parents, the son of a centurion, and trained as a lawyer.  After he became a Christian believer, he wrote a defence of the faith against pagans and heresies. He was probably the first person to use the phrases ‘one substance, three persons‘ to describe the Trinity (God as Father, Son and Holy Spirit), and ‘one person, two substances‘ to explain who Jesus was.

One of the greatest writers In the early third century was Origen.  He was a prolific philosophical writer, although he propounded some rather extreme doctrines which were later rejected by some parts of the church.

More church history pages:

Church history begins
Paul’s Missionary Journeys
Early church persecutions
Christian martyrs in the third century
Constantine and the Council of Nicea