Question about Church History

What was the most dangerous/notorious heresy in Church history and why? Arianism? Catharism? Something else?

Thanks in advance and God bless.

The most dangerous heresy is the one that is currently infecting the Church - Modernism. Pope St. Pius X condemned it in his Encyclical “Pascendi Dominic Gregis”, but now it is rife in the Church. It is worse than the heresies of Arianiam, Protestantism and all the rest. In fact, St. Pius X called it the “Synthesis of all Heresies”, that’s how dangerous it is.

Modernism basically is akin to the Freemasons, that is, they teach that morals can change, teachings can change and that all the miracles in the Gospels were not real miracles. There are even “Catholic” Bishops saying this publicly!

God bless.

Good point, but I didn’t mention that since it’s ongoing while others we can look at in hindsight and say which was worse.

I say this as someone who is still Protestant. The Reformation. :wink:


Protestantism was the single most successful heresy ever (unless you consider Islam a heresy too… then it would be Islam).

Protestantism’s ultimate outcome is the mess we have today in the west. When people become their own religious authority, you get what we have today.

However, the Catharism was physically the most damaging to each individual affected. They believed that matter was evil and believe that it was sinful to have children and promoted ritualistic suicide. They also had a lot of other twisted beliefs. Had they grown in size, it would have been the most dangerous. But thankfully, with God’s help, we put an end to that.

No offense to the Protestants here, but definitely Protestantism, as it has proven to be the longest lasting and most divisive.

Well, there is no Baptism in Islam nor do they adopt the Christian name so I don’t think Islam would count as a heresy. But in way it can be seen as some sort of Arabised Proto-Protestantism.

What you said about the Cathars is really the type of answers I’m looking for, since the heresy itself is now history (thank God).

What is similar about the Jesuit and Dominican Orders?
Well, they were both founded by Spaniards, St. Dominic for the Dominicans, and St. Ignatius of Loyola for the Jesuits.
They were also both founded to combat heresy: the Dominicans to fight the Albigensians, and the Jesuits to fight the Protestants.

What is different about the Jesuit and Dominican Orders?
Well, have you met any Albigensians lately?

*Note: *This joke is obviously told from a Dominican perspective. The Jesuit response would be: “That’s because we didn’t use swords!”]

Not sure, but there are great ones like:

  1. Arianism, 2. the Eastern Orthodox schism, 3. the Protestant Rebellion, and 4. today (not sure the name, maybe “Post-modernism” or just “modernism”).

Today, there are too many dissents, like applying modern ideals to Church teaching (like thinking that we are always right and the Church is probably wrong, even when people don’t want to research the logic in the Church’s teachings)
or going too far as to go into schism with the Pope, like sedevacantism and the SSPX.

If I am wrong, someone correct me, I heard this list from Church Militant.

Modernism as defined by the media. The media models bad and immoral behaviors. Every bad/immoral/indecent image we see in a magazine and written immorality in books. Even comic books are promoting heroes who are not heroic, women who are less than decent. This combined with a news media that believes immorality is good or neutral. “It’s just the way it is.” That’s a lie. Anyone can create media without the profanity, without the sexual situations and without anti-Christian images and messages. But the poison took decades of promotion since those involved knew that we could not go from Leave it to Beaver to Two and Half Men overnight. The poison was dripped into our veins slowly. More and more people were influenced by the media preaching immorality. And the Catholic Church? A joke. Backwards. Irrelevant. Religion is “too demanding” for some, but we need it.

Everything we hear, see and read affects us on some level. Without a firm understanding of right and wrong, we can be and are misled. We end up believing people who like immorality.


Yes by killing them

Correct me if I’m wrong, but weren’t the Cathars incredibly dangerous? For example, killing missionaries sent to them?

No I think you will find that they were exceptionally peaceful. It has been long held as nothing short of murder they way the medieval church treated cathars. This may help a little

There is NOTHING original about Protestantism. In fact Protestantism is a “Reader’s Digest” of ALL the ancient heresies repackaged into one big heresy hydra! :wink:

What was the relationship between the Bogomils and Cathars BTW?

From Catholic Answers:

The Great Heresies

From Hillaire Belloc:

The Great Heresies
(This is the full text of his book)

Belloc includes:

*]The Arian Heresy
*]The Great and Enduring Heresy of Mohammed
*]The Albigensian Attack
*]What Was the Reformation?
*]The Modern Phase

What group(s) PRIOR to Luther held the doctrines of sola scriptura or sola fide?

While the original heresies didn’t go by those names specifically, make no mistake, the ancient heretics preferred Scripture to Church teaching, or at least their own interpretation of it. Then there is St. James’ Letter which even THEN was being written to counter the then current heresy of Faith alone based on the misreading of St. Paul’s letters. St. Augustine was arguing with variations on SS and SF even in his own time. The more one studies the ancient heresies, the more one sees nothing new in Protestantism. :wink:

And like the hydra, every time one of its heads is cut off (proved false) multiple new heads appear that seem to be something different.

So for example today Lutherans are very prickly about SS and FA. They claim they don’t REALLY hold fast to those, but rather tradition, their confessions etc. Even though their fundamentalist brethren are quite comfortable with raw SS and FA.

To be fair, that’s not really true. Yes, Protestantism has some similarities with previous heresies, but they are not a repackaging.

Some heresies denied the Divinity of Christ, denied the existence of the Holy Spirit, considered physical matter and life forms to be evil, etc.

Protestantism accepts the Trinity and for the most part the nature of Jesus Christ.

However, Protestantism is heretic because it misunderstands the Church, the Sacraments, the full Deposit of Faith, salvation, etc. But many other heresies denied the Nature of God.

I recommend you buy and listen to

The 2nd CD in the package deals with the Inquisition, and there they talk about some of the early heresies, like the Albigensians.

I think you would really enjoy this CD set, I know I have.

God Bless

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