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What Does Heresy Mean? Biblical Definition & Historical Examples

A heresy is any belief or practice that explicitly undermines the gospel. The identification and condemnation of heresies have played a significant role in shaping the development of Christian theology.

Updated Feb 07, 2024
What Does Heresy Mean? Biblical Definition & Historical Examples

Heresy is any belief or theory that strongly opposes established beliefs or customs, particularly the accepted beliefs or religious law of a religious organization. Within Christianity, it is any belief or practice that explicitly undermines the gospel. It is a threat to the unity and orthodoxy of the faith, and historically, the identification and condemnation of heresies have played a significant role in shaping the development of Christian theology. Learn the Greek definition of heresy, biblical and historical examples, and the difference between heresy and blasphemy.

According to Easton's Bible Dictionary, the word heresy comes from a Greek word, meaning a self-chosen opinion or the sect holding that opinion. Heresies came to be understood as self-chosen doctrines that do not originate from God. 

What Is Heresy?

Heretical beliefs are considered a departure from the accepted and authoritative teachings of Christian tradition. Heresy is typically an internal challenge within a religious community, as it pertains to deviations from official doctrines. The identification and condemnation of heresy have historically been addressed through theological debates, councils, and doctrinal statements.

However, referring to a person as a heretic or to an idea as heretical is a powerful claim, one with the ability to destroy. And like all weapons of mass destruction, it should be used with extreme caution. Calling something a heresy when it doesn’t contribute to other serious problems for the church today. How can true heresy be determined?

1. It’s not a heresy just because it’s wrong.

I can be wrong about lots of things without undermining the gospel itself. If that wasn’t the case, I’d be undermining the gospel with almost every thought. (I make a lot of mistakes.)

2. It’s not a heresy just because it might undermine the gospel.

There’s a difference between things that clearly undermine the biblical gospel (e.g. denying the deity of Christ) and things that could possibly undermine the gospel depending on how exactly you understand them (e.g. the relationship of faith and works). The church has generally been rather careful about using the label heresy, restricting it to beliefs in the first category, not the second.

3. It is indeed a heresy if it explicitly undermines the gospel. 

At the end of the day, the church has been hesitant to call something heresy unless it has been determined by some authoritative body that the belief in question explicitly undermines the gospel itself.

When duly designated ecclesial authorities have determined together that a belief explicitly undermines the truth of the gospel, as the church decided with heresies like Arianism and Pelagianism, we should not shy away from calling them what they are. To do less isn’t humble, it’s irresponsible.

The problem isn’t with the concept of heresy but with the ways that we have misused and abused the concept. While trying to search out errors in the church, we haven’t been as mindful of the fact that the way we use the heresy label can create its own errors, some equally as dangerous as the ones we had in mind, to begin with.

Examples of Heresy in Christian History

These heresies significantly impacted Christian history by prompting theological debates, leading to the formulation of key doctrinal statements in ecumenical councils, and shaping Christian orthodoxy. The struggles against heresy were instrumental in defining and refining the core tenets of the Christian faith.

Arianism (4th century)

Belief: Arianism, associated with the priest Arius, challenged the orthodox Christian understanding of the Trinity. Arius denied the full divinity of Jesus Christ, asserting that Jesus was a created being and not co-eternal with God the Father.

Impact: Arianism posed a serious threat to the unity of the early Christian Church. The controversy led to the First Council of Nicaea in 325 AD, where the Nicene Creed was formulated, affirming the consubstantiality of the Father and the Son. While Nicaea condemned Arianism, the controversy persisted for decades, influencing imperial politics and shaping the theological landscape.

Nestorianism (5th century)

Belief: Nestorianism, named after Nestorius, separated the divine and human natures of Jesus to an extent that implied two distinct persons rather than one united person. Nestorius's teachings were condemned at the Council of Ephesus in 431 AD.

Impact: The Nestorian controversy contributed to the ongoing theological debates about the nature of Christ. The Council of Ephesus affirmed the orthodox understanding of the hypostatic union, which emphasizes the inseparable unity of Christ's divine and human natures in one person. The controversy also played a role in the division between Eastern and Western Christianity.

Gnosticism (1st-2nd centuries)

Belief: Gnosticism comprised various sects with diverse beliefs, but in general, Gnostic teachings emphasized secret knowledge and spiritual enlightenment, challenging mainstream Christian views on creation, salvation, and the nature of God.

Impact: Gnosticism posed a challenge to the early Christian Church by introducing alternative cosmologies and salvation narratives. Early Christian leaders, including Irenaeus and Tertullian, wrote against Gnostic ideas. The battle against Gnosticism influenced the development of Christian doctrine, reinforcing the importance of apostolic tradition and the canon of Scripture. The struggle against Gnostic influences also shaped early Christian mysticism and asceticism.

Heresy vs Blasphemy

Blasphemy is any word or deed that insults God, Jesus Christ, the Holy Spirit, sacred doctrines, or religious symbols. The concept is rooted in the biblical commandment against taking the name of the Lord in vain (Exodus 20:7), and it reflects a deep respect for the sacred and divine.

Blasphemy is often a broader and external concept, as it may involve actions or expressions that challenge or insult religious sensibilities from outside the faith community. It can have legal consequences in some jurisdictions, and historically, it has been considered a moral and social offense.

Heresy primarily deals with incorrect beliefs or teachings within a religious community, challenging established doctrines. Blasphemy, on the other hand, focuses on disrespectful or irreverent actions or expressions directed toward a religious community. Both concepts reflect challenges to religious orthodoxy, but they manifest in different ways, by different people, and address different aspects of faith and reverence of the Gospel.

Heresy in the Bible: False Teaching

False Prophets and Teachers ~ 2 Peter 2

But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction. And many will follow their sensuality, and because of them the way of truth will be blasphemed. 3 And in their greed they will exploit you with false words. Their condemnation from long ago is not idle, and their destruction is not asleep. For if God did not spare angels when they sinned, but cast them into hell and committed them to chains of gloomy darkness to be kept until the judgment; if he did not spare the ancient world, but preserved Noah, a herald of righteousness, with seven others, when he brought a flood upon the world of the ungodly; if by turning the cities of Sodom and Gomorrah to ashes he condemned them to extinction, making them an example of what is going to happen to the ungodly; and if he rescued righteous Lot, greatly distressed by the sensual conduct of the wicked (for as that righteous man lived among them day after day, he was tormenting his righteous soul over their lawless deeds that he saw and heard); then the Lord knows how to rescue the godly from trials, and to keep the unrighteous under punishment until the day of judgment, and especially those who indulge in the lust of defiling passion and despise authority. Bold and willful, they do not tremble as they blaspheme the glorious ones, whereas angels, though greater in might and power, do not pronounce a blasphemous judgment against them before the Lord. But these, like irrational animals, creatures of instinct, born to be caught and destroyed, blaspheming about matters of which they are ignorant, will also be destroyed in their destruction, suffering wrong as the wage for their wrongdoing. They count it pleasure to revel in the daytime. They are blots and blemishes, reveling in their deceptions, while they feast with you. They have eyes full of adultery, insatiable for sin. They entice unsteady souls. They have hearts trained in greed. Accursed children! 

Forsaking the right way, they have gone astray. They have followed the way of Balaam, the son of Beor, who loved gain from wrongdoing, but was rebuked for his own transgression; a speechless donkey spoke with human voice and restrained the prophet's madness. These are waterless springs and mists driven by a storm. For them the gloom of utter darkness has been reserved. For, speaking loud boasts of folly, they entice by sensual passions of the flesh those who are barely escaping from those who live in error. They promise them freedom, but they themselves are slaves of corruption. For whatever overcomes a person, to that he is enslaved. For if, after they have escaped the defilements of the world through the knowledge of our Lord and Savior Jesus Christ, they are again entangled in them and overcome, the last state has become worse for them than the first. For it would have been better for them never to have known the way of righteousness than after knowing it to turn back from the holy commandment delivered to them. What the true proverb says has happened to them: "The dog returns to its own vomit, and the sow, after washing herself, returns to wallow in the mire."

Bible Verses about Heresy

As for a person who stirs up division, after warning him once and then twice, have nothing more to do with him ~ Titus 3:10

Beloved, do not believe every spirit, but test the spirits to see whether they are from God, for many false prophets have gone out into the world. ~ 1 John 4:1

But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction. ~ 2 Peter 2:1

For if someone comes and proclaims another Jesus than the one we proclaimed, or if you receive a different spirit from the one you received, or if you accept a different gospel from the one you accepted, you put up with it readily enough. ~ 2 Corinthians 11:4

If anyone comes to you and does not bring this teaching, do not receive him into your house or give him any greeting ~ 2 John 1:10

Not that there is another one, but there are some who trouble you and want to distort the gospel of Christ. ~ Galatians 1:7

How Did the Early Church Handle Heresy?

Heresy was a problem since the early church. Alister McGrath said this about the early church and its way of handling ideas – even some heretical ones.

“It’s about discernment. And what the early church did was to say that we are under obligation to give the best account of what we find in Scripture. It’s very important to do this properly.”

Marc Cortez is a theology professor at Wheaton College, husband, father, & blogger, who loves theology, church history, ministry, pop culture, books, and life in general. Visit him at marccortez.com.

This article was adapted from “3 Reasons We Should Stop Calling People Heretics…Unless They Are” by Marc Cortez.

Photo Credit: ©Thinkstock/Deagreez


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