Homoianism: When the Heretics Won

The Story

This is the story that most Christians never learn, and it is arguably the most important one in the entire history of Christian doctrine. For roughly twenty years — from 360 to 380 AD — the official, imperially enforced Christianity of the Roman Empire was not what we now call “orthodox.” The Nicene Creed, that bedrock formula recited every Sunday by billions, was the condemned minority position. Its champions were exiled, tortured, and deposed. The emperors backed its opponents. The majority of bishops signed documents repudiating it. Jerome, writing a few decades later, captured the shock in one devastating sentence: “The whole world groaned and was astonished to find itself Arian.”

To understand how this happened, you need to understand that the Council of Nicaea in 325 did not settle anything. It produced a creed containing the word homoousios (“of the same substance”), but that word was controversial from the start. Many eastern bishops considered it philosophically suspect — it had been used by Paul of Samosata, a condemned heretic, and it sounded dangerously close to modalism (if Father and Son share the same substance, are they really distinct?). The word ousia (“substance” or “essence”) was itself ambiguous. In common Greek usage, ousia and hypostasis meant roughly the same thing. So when the Nicene Creed said the Son was “of the same ousia” as the Father, many bishops heard “of the same hypostasis” — which sounded like it was saying Father and Son are the same person. This was not paranoia; it was a genuine linguistic problem that would take the Cappadocian Fathers decades to untangle.

The anti-Nicene reaction began almost immediately. Emperor Constantine himself, who had convened Nicaea, grew sympathetic to Arius’s supporters in the years before his death in 337. His son Constantius II, who ruled the eastern empire from 337 and the whole empire from 353, was firmly anti-Nicene. Constantius saw the homoian position — the Son is “like” (homoios) the Father, full stop, no substance language — as the ideal theological compromise. It avoided the modalist-sounding homoousios, avoided the radical Arian anomoios (“unlike”), and seemed to offer a formula that everyone could sign. Constantius backed this position with the full weight of imperial power.

The critical moment came at the twin councils of Rimini (in the West) and Seleucia (in the East) in 359. At Rimini, approximately 400 western bishops initially affirmed the Nicene position. But the imperial commissioner refused to let them leave until they signed a homoian creed — the so-called “Dated Creed” of Nike (a suburb of Rimini), which declared the Son “like the Father” and banned all substance language as unbiblical. After months of pressure, threats, and what amounted to imprisonment, the bishops broke. They signed. The eastern council at Seleucia produced a similar result. In 360, a council at Constantinople ratified the homoian creed as the official faith of the empire. The Nicene position was formally condemned. Athanasius was in his third exile. Pope Liberius of Rome had been arrested, exiled, and — according to some sources — signed a semi-Arian formula under duress (the degree of his capitulation is still debated by historians).

This is the world Jerome was describing. The homoian position was not a fringe heresy; it was the imperially enforced mainstream. Nicene bishops were deposed and replaced. Congregations that held to homoousios met in secret or in private homes. The theological situation of 360-380 AD was, in effect, the reverse of what we now consider normal: the “heretics” held the cathedrals and the “orthodox” were the underground church.

The resolution came through a combination of theology and imperial politics. Theologically, the Cappadocian Fathers — Basil of Caesarea, Gregory of Nazianzus, and Gregory of Nyssa — solved the linguistic problem that had made homoousios so controversial. They drew a sharp distinction between ousia (essence — what God is) and hypostasis (person — who each of the three is). One ousia, three hypostaseis. This formula preserved the real distinction between Father, Son, and Spirit (answering the modalism concern) while affirming their complete unity of essence (answering the Arian concern). Crucially, it also built a bridge to the homoiousians — the “semi-Arian” middle party who affirmed “similar substance.” Athanasius himself had recognized that the homoiousians were close allies, separated by barely an iota. The Cappadocian formula gave the homoiousians a way to affirm homoousios without feeling like they were collapsing into modalism.

Politically, the shift came when Emperor Theodosius I took power in 379. Theodosius was a westerner, baptized in the Nicene tradition, and he had no patience for the homoian establishment. In 380, he issued the Edict of Thessalonica, declaring Nicene Christianity the official religion of the empire. In 381, he convened the Council of Constantinople, which reaffirmed and expanded the Nicene Creed into essentially the form recited today. The homoian bishops were deposed. The twenty-year experiment in imperially enforced non-Nicene Christianity was over.

What the Council Actually Said

The theological spectrum of the fourth century was not a binary but a gradient, distinguished by a single Greek prefix:

• Homoousios (ὁμοούσιος) — “same substance.” The Nicene position.
• Homoiousios (ὁμοιούσιος) — “similar substance.” The semi-Arian middle ground.
• Homoios (ὅμοιος) — “like.” The homoian position. No substance language at all.
• Anomoios (ἀνόμοιος) — “unlike.” Radical Arianism (Aetius and Eunomius).

The Dated Creed of Nike/Rimini (359) declared:

“We believe in one only and true God, the Father Almighty… and in one only-begotten Son of God… like the Father who begot him, according to the Scriptures… but whereas the term ‘substance’ (ousia) has been adopted by the Fathers in simplicity, and gives offense as being unknown to the people because it is not contained in the Scriptures, it has seemed good to remove this term.” — Creed of Nike/Rimini, 359 AD

This creed did not say the Son was unlike the Father — it was not radical Arianism. It said the Son was “like” the Father and then banned all substance language as unbiblical. It was a theological ceasefire that happened to disarm the Nicene side completely.

Jerome’s famous lament, written in his Dialogue Against the Luciferians around 382, captured the aftermath:

“The whole world groaned and was astonished to find itself Arian.” — Jerome, Dialogue Against the Luciferians, c. 382 AD

Why You Might Accidentally Believe This

The homoian instinct — “let’s just say Jesus is like God and not get bogged down in philosophical jargon” — is extremely common in modern Christianity. Any time someone says “I don’t care about theology, I just love Jesus” or “Can’t we just stick to what the Bible says without all this Greek philosophy?” they are, functionally, taking the homoian position. The homoians’ central argument was that ousia language was unbiblical and divisive. That argument resonates deeply with many Protestants today who are suspicious of creedal formulations that go beyond explicit biblical vocabulary.

Many evangelicals, if pressed, would describe Jesus as “like” the Father — similar, reflecting God’s character, doing God’s work — without affirming the specific Nicene claim that the Son is “of the same substance” as the Father. This is not because they have studied the fourth-century debates; it is because the homoian position is the natural resting place for anyone who wants to affirm Christ’s divinity without doing metaphysics.

The Strongest Case For This View

The homoians had a genuinely powerful argument: the word homoousios appears nowhere in the Bible. It is a philosophical term borrowed from Greek metaphysics and imposed on the biblical witness. The homoians argued that Christians should describe God only in biblical language, and the Bible says the Son is the “image” of God (Colossians 1:15), the “radiance” of God’s glory (Hebrews 1:3), “like” the Father in every way that matters. Why insist on a non-biblical word that was causing the church to tear itself apart?

There was also the modalism problem. If Father and Son share the same ousia, and ousia means what most Greek speakers thought it meant, then Father and Son are the same individual thing — which collapses the distinction between the persons. The homoiousians (“similar substance”) and homoians (“like”) were both trying to preserve the real distinction between Father and Son that the New Testament clearly depicts. Jesus prays to the Father. The Father sends the Son. These are relational descriptions that require two distinct agents, and many eastern bishops genuinely feared that homoousios flattened that distinction.

Finally, the homoian position was a genuine attempt at church unity. The fourth century was tearing itself apart over a single word. The homoian formula offered a big tent: affirm that the Son is like the Father according to the Scriptures, drop the divisive philosophical vocabulary, and let Christians get on with being Christians. It was wrong — but it was not stupid, and it was not malicious.

The Strongest Case Against

The Cappadocian Fathers and the pro-Nicene party argued that “like” is fatally vague. Anything can be “like” something else in some respect. A photograph is “like” a person. A dog is “like” its owner. Saying the Son is “like” the Father tells you nothing about whether the Son is actually divine. The whole point of homoousios was precision: not just “like” God, but sharing the same divine essence. Without that, you can affirm that the Son is “like” the Father while secretly (or openly) holding that the Son is a creature — which is exactly what the radical Arians did.

The ban on substance language was also suspicious. If the homoians genuinely believed the Son was fully divine, why would they object to saying so in the clearest possible terms? Removing ousia from the vocabulary did not create peace; it created an ambiguity that the Arian party could exploit. Athanasius argued that the homoian formula was not a compromise but a Trojan horse — a way of making Arianism respectable by refusing to say anything definite enough to be tested.

The Cappadocian solution — one ousia, three hypostaseis — showed that homoousios did not require modalism. You could affirm that Father, Son, and Spirit share the same divine essence while insisting they are three distinct persons in eternal relation. Once that distinction was clearly articulated, the homoian objection lost its force.

What the New Testament Actually Says

The New Testament uses “likeness” language about the Son, but it also goes further. Hebrews 1:3 says the Son is the “exact imprint” (charakter) of God’s very being (hypostasis). Colossians 2:9 says “in him the whole fullness of deity dwells bodily.” John 1:1 says the Word “was God” — not “was like God.” These texts push beyond mere likeness toward identity of nature.

But the homoians were right about one thing: the New Testament does not use the word homoousios, and it does not systematically explain the metaphysical relationship between Father and Son. The conciliar language is an interpretation of the biblical data, not a direct quotation. The question is whether it is a faithful interpretation — whether “of the same substance” is the best way to hold together what John 1:1 and John 14:28 are both saying. The Nicene-Constantinopolitan tradition says yes. The homoians said no. And for twenty years, the homoians had the cathedrals, the emperor, and the majority of bishops on their side.

The resolution was not inevitable. It took brilliant theology, imperial regime change, and a generation of work. That should give every Christian pause about assuming that correct doctrine is always obvious or that the right side always wins quickly.

Further Reading

• Arianism — the radical position the homoians tried to distance themselves from
• Nicene Trinitarianism — the condemned minority position during the homoian ascendancy
• Subordinationism — the broader theological family
• Anomoeanism — the radical “unlike” wing that made the homoians look moderate
• The Council of Rimini — the story of 400 bishops breaking under pressure
• When “Orthodox” Was Heretical