- by Carrie Shaw
- on March 22, 2026
The Heresies Of Docetism And Arianism
Two theological truths about Christ were recognised and held together as essential in the early church: that Jesus is truly human and truly divine.
However, two major heresies arose that challenged these truths: Docetism and Arianism.
Docetism claimed that Jesus wasn’t really human, that he only appeared to be human, challenging the essential reality that Jesus really did experience humanity in every way like us, yet without sin.
Arianism claimed that Jesus wasn’t truly divine in the same way that God Himself is divine, instead presenting the Son as the first and greatest creation of God. This challenged the monotheism that lies at the heart of the Christian faith. (If the Son is a created being, yet receives the worship, honour, and authority given to him throughout the New Testament, it raises a difficult question: how can such devotion remain consistent with the belief that there is only one God?)
Both these heresies are worth exploring in more detail to understand what was being proposed, what the implications were, and why these questions still matter for how we understand Jesus today.
Who Is Jesus?
If there’s one thing we learn from the writings of the early church, it’s that we don’t get to invent who Jesus is.
Knowing who we worship and who saves us lies at the heart of the gospel, giving shape and depth to the truth that “we are saved by grace through faith.” We have a mighty saviour, one who can both intercede on our behalf, having truly suffered in his humanity, but who was also powerful enough to overcome death, bringing life to all who would trust in his name.
The early church worshipped and honoured Jesus, affirming both his divinity and his humanity; truly God and truly man.
This high Christology can be found throughout Scripture, perhaps nowhere so beautifully expressed as in the early chapters of John, in his prologue concerning the Word made flesh. Where the other three gospel writers spend time on more practical matters, such as Jesus’ ancestry, town of birth and insights into his early childhood, John offers none of this. Instead, he begins his gospel “in the beginning“, an obvious allusion to the time before creation, before the dawn of history, right in the heart of God Himself.
“In the beginning was the Word, and the Word was with God and the Word was God…and the Word became flesh and dwelt among us.“
The miracle of the incarnation is the moment in history where the invisible God was made visible, the glory of deity wrapped in skin and bone – the perishable covering that humanity now wears.
As Paul the Apostle later writes in Philippians, “Jesus, who being in very nature God, did not consider equality with God something to be used to his own advantage, rather, he made himself nothing by taking the very nature of a servant, being made in human likeness, and being found in appearance as a man, he humbled himself by becoming obedient to death, even death on a cross.” (Philippians 2:6-8).
The Word, through whom all things were created, who was before all things, and in whom all things hold together (Colossians 1:15-17), stepped into human history to reconcile and redeem it, going even so far as death itself for our sake.
The reality of who Jesus was and what he had done lay at the very heart of orthodoxy, the foundation stone of the church that would be built in his name.
This confession – the full humanity and the full divinity of Jesus – was written into Scripture, taught by those who took the gospel to foreign shores, confirmed by creeds, and guarded carefully by the early church, who understood that deviating from this truth would open the door to heresies and misinterpretations about the one they called Lord and Christ.
What Was Docetism?
Docetism emerged in the second century and was closely connected to aspects of Gnostic thought, which viewed the created, natural world as corrupt or inferior, while considering the spiritual realm as pure and good. In that framework, human bodies were seen as something to escape rather than something God had intentionally created as part of His good world.
Jesus, in the view of Docetists, couldn’t have been physically human, since a divine being would never take on corrupt human flesh, but must have only appeared to be human. Notice here that there is no argument regarding the divinity of Jesus, only his true humanity.
Docetists believed that Jesus’ physical body, sufferings, death, and even resurrection weren’t real, because he himself wasn’t truly human; they only seemed to be real. (The name ‘Docetist’ comes from the Greek word meaning to seem or to appear).
The implications of this teaching are serious. If Jesus wasn’t truly human, in every way that it means to be human, then he didn’t really share with us in our humanity, he didn’t truly suffer, and he didn’t truly die, realities that directly affect the atonement.
Docetism, however, is directly challenged by the Gospels and later the Apostles, who, by contrast, strongly emphasise the humanity of Jesus.
The account of Jesus’ arrival in two of the gospels is preceded by a recounting of his genealogy, stretching back to David and Abraham in one, and to Adam himself in another. Both authors go to great lengths to emphasise Jesus’ connection to humanity from the very beginning, and that he was literally born into the human family.
The stories of Jesus’ ministry likewise emphasise his human experiences; hunger, sadness, exhaustion, pain, and grief. He eats with his disciples, sleeps in the boat, weeps at Lazarus’ tomb, and agonises in prayer before the cross. The gospel writers aren’t hesitant about these details. On the contrary, they highlight them, reminding us again and again that the one who walked among them was not merely appearing to be human; he truly was human.
Even the account of his death is heartbreaking in its realness. His agony, shame, bleeding, and eventual cruel and painful death are recorded plainly by the gospel writers, leaving us in no doubt that the suffering of the cross was fully and tragically real.
Scripture affirms the full humanity of Jesus, teaching that Jesus didn’t merely ‘appear’ as some kind of disembodied, holographic spirit but fully became one of us (1 John 4:2, Hebrews 2:14-17, Colossians 2:9, Romans 8:3). Jesus had an actual body; he was physically among us and with us, truly human in every way. Anyone who did not confess this truth was, as 2 John 7 comments, a deceiver. By contrast, every spirit that acknowledged “that Jesus Christ has come in the flesh is from God.” (1 John 4:2)
What The Early Church Confessed
Ignatius, a contemporary of Polycarp, who was himself a disciple of John of the Revelation, is one of the earliest and strongest voices against Docetism. Writing only a generation after the apostles, he repeatedly emphasised that Christ’s suffering was real.
In Letter to the Smyrnaeans he writes: “Jesus Christ… was truly born, and ate and drank; he was truly persecuted under Pontius Pilate; he was truly crucified and died.”
Ignatius stresses the word “truly” again and again to push back against those who were claiming that Jesus only appeared human.
Irenaeus (AD130-202), a disciple of Polycarp, also opposed several Gnostic groups that promoted Docetic ideas. He explicitly said he learned from Polycarp and heard him speak about what he had received from the Apostle John. This is one of the clearest links we have from the apostolic generation to the second-century church, which is why Irenaeus is such an important witness when looking at early Christian belief.
In Against Heresies, he argues that salvation depends on Christ’s real humanity: “If he did not truly take flesh, he did not truly redeem us.”
And finally, although not exhaustively, Tertullian, writing around 206 AD, argued in his work On the Flesh of Christ that denying Christ’s real body destroys the gospel: “If Christ had not truly suffered, he had not truly died; and if he had not truly died, he had not truly risen.”
Tertullian insisted that the incarnation and the cross must be understood as real historical events, not appearances, for the gospel to have saving power.
What Was Arianism?
Arianism was a whole other thing. While it didn’t deny that Jesus came in the flesh – the incarnation and reality of Jesus’ humanity were never in question; it presented another challenge altogether. Arius (from whom the heresy of Arianism is named) taught that the Son was the first and greatest creation of God. While Arians spoke of Jesus as divine, it wasn’t in the same sense as God. He was a supreme created being rather than sharing in the divine nature of the Father.
This, of course, undercuts both the fullness of the incarnation and the central biblical teaching of monotheism: that there is only one God, and that He alone is worthy of worship.
While Arians fully affirmed the incarnation, the problem was who the Son actually was. In Arian teaching, because the Son was not the eternal God but rather the first and greatest creation of God, this meant that when the Word became human, it wasn’t God Himself entering human history, but a created and subordinate divine being. In that sense, the incarnation is fundamentally altered.
Christianity proclaims that God became human; Arianism ultimately replaces this with something else, the idea that a lesser heavenly being became human.
And this, again, presents a problem when we come to the gospel records and the teaching of the apostles, particularly the writings of Paul.
Firstly, Jesus himself makes claims and accepts honours that, in the Jewish context, belong to God alone; the use of divine language in John 8:58, which echoes God’s self revelation in Exodus 3:14, his declared authority over all things in heaven and on earth, authority which belonged to God alone (Matthew 28:18), and his statement of oneness with the Father, words which led his listeners to accuse him of claiming to be God, an accusation he neither refuted nor corrected (John 10:30–33).
His control over both the natural and spiritual worlds, walking on water, healing disease, forgiving sins, and commanding even the forces of nature; all of these actions and claims pointed in the same direction: the gospel writers present Jesus as sharing in the authority, identity, and power that belong to God Himself.
Jesus also identifies himself in Revelation using divine titles, calling himself “the First and the Last” and “the Alpha and the Omega,” language that belongs to God Himself (Revelation 1:17–18; 22:13) and titles which echo Isaiah 44:6, where the Lord says, “I am the first, and I am the last; apart from me there is no God.”
Scripture never introduces Jesus as a lesser divine being, but rather as the Word made flesh, sharing in the identity of the one God of Israel.
Interestingly, what was being claimed by Arius was not that Jesus wasn’t divine, but that he wasn’t the same kind of divine as God the Father. This is why the discussions at the First Council of Nicaea focused so intensely on the wording used to describe Christ. The council wrestled particularly with the phrase “of the same substance” (homoousios), which appears in the Nicene Creed.
It is an egregious misrepresentation to say that the divinity of Christ was invented in the fourth century. Rather, the heresy that arose was the suggestion that Christ was less than divine, or perhaps a different kind of divine than what the church had always taught and affirmed. If you were someone who was told the Trinity was invented and formalised at the Council of Nicaea, this is simply not true. You can read more about that here.
What The Early Church Confessed
Ignatius referred to Jesus explicitly as “our God, Jesus Christ”, echoing the worship of Thomas in the Gospel of John (20:28), who addresses Jesus as “my Lord and my God“. In fact, Ignatius repeatedly refers to Jesus in this way, writing, for example, in his letter to the Ephesians, that “our God, Jesus Christ, was conceived by Mary according to God’s plan.”
Ignatius lived well before the Arian controversy, centuries before the Nicene Creed, and yet he refers to Jesus repeatedly as “our God, Jesus Christ,” demonstrating that the worship of Christ as truly divine was not a later invention but part of the early Christian faith.
Justin Martyr, writing around 150 AD, described Christ as the pre-existent Logos, distinct from the Father yet divine. He defended the worship of Jesus and spoke of the Spirit sharing in divine honour.
Irenaeus, whom we met earlier, spoke clearly of Christ in divine terms. He writes of “Christ Jesus our Lord, and God, and Saviour, and King,” and, like Ignatius before him, places Jesus within the identity and worship of the one true God.
Another early Christian witness is Melito, the bishop of Sardis (one of the seven churches of Revelation), who probably wrote around 160-180 AD. He was well known in the early church as a respected teacher and apologist. In one of his works that survives, he reflects on the crucifixion, where he says:
“The one who hung the earth in place is hanging.
The one who fixed the heavens has been fixed with nails.
The one who set the earth in place is set upon a tree…
God has been murdered.”
(Peri Pascha – On The Passover)
Interestingly, the understanding of the pagans was also that the Christians “sing to Christ as to a god” (this comes from Pliny the Younger circa 112 AD), a description the church itself never attempted to correct.
Importantly, the church never worshipped Jesus as a lesser deity or some kind of demigod, but saw their worship of Jesus as continuing to uphold the monotheism of the ancient Jewish faith.
In a context where many people believed in layers of divine or semi-divine beings between God and the world, (such as angels, spiritual rulers, or intermediary powers), the early Christian church, particularly the writings of Paul the Apostle, places Jesus above and outside that system entirely. In passages like Colossians 1, Paul doesn’t present Jesus as one divine or semi-divine being among many, nor as a created heavenly intermediary between God and humanity. Instead, he describes Jesus as the one through whom all things were created, including those very powers, and the one in whom the fullness of God dwells.
Why The Early Church Taught A Robust Christology And Why It Still Matters Today
At this point, you might be wondering why any of this matters. These are ancient heresies, after all; historical debates that seem far removed from everyday life. But the truth is, the questions they raised have never really gone away.
A robust Christology is therefore vitally important for the questions we still ask today. Who is Jesus? How does Scripture present him to us? What did the early church teach about him? What does this mean for the world? And, perhaps, most importantly, what does this mean for me?
Scripture presents Jesus as the centre of all things. The Old Testament points forward to his arrival, the promised one, the greater than Adam, who would redeem humanity and reconcile all creation to God. His coming was not merely the arrival of a messenger, but the arrival of God Himself (Isaiah 40:3, Isaiah 9:6, Malachi 3:1, Zechariah 2:10).
The New Testament is the witness of that arrival. As John the Baptist proclaimed, “Prepare the way for the Lord” (John 1:23), echoing the words of the prophet Isaiah, a prophecy that originally spoke of preparing the way for God Himself (Isaiah 40:3).
The Christian gospel is one of good news, that the God who created us and loves us is also the God who is actively working to reconcile us and free us from sin and death, a promise He made long ago. That promise finds its fulfilment in Jesus. Because he is truly human, he represents humanity. Because he is truly divine, he has the authority and power to save.
Both Docetism and Arianism directly impacted this core gospel truth. And that’s why Christians throughout history have wrestled so carefully with the question of who Jesus truly is and why the conversation is still relevant.
Today, some portray Jesus merely as a moral teacher or inspired prophet rather than the eternal Son of God. Others affirm his historical existence but reinterpret the resurrection as symbolic rather than a real historical event. Still others present him as a divine figure who only seemed to share in our humanity, or as some kind of cosmic spiritual force rather than the incarnate Son of God.
Yet all of these versions of Jesus fall short of the Jesus presented in Scripture, the One who is the centre and heart of the gospel of good news. And when we misunderstand that centre, we’re in danger of affirming a Jesus who simply cannot do what the gospel says he came to do.
