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Heresy

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Heresy is a word for ideas that go against established beliefs. It usually refers to ideas that disagree with religious laws or customs.

Maker unknown, Sino-Tibetan - Acarya Bhavaviveka Converts a Nonbeliever to Buddhism - Google Art Project
Maker unknown, Sino-Tibetan - Acarya Bhavaviveka Converts a Nonbeliever to Buddhism - Google Art Project

The word comes from the Ancient Greek word "haíresis." This originally meant "choice" or "a thing chosen." Later, it meant the school of thought a person chose. A person who holds these ideas is called a heretic. The leader of such a movement is called a heresiarch.

Galileo facing the Roman Inquisition
Galileo facing the Roman Inquisition

It is different from apostasy, which is leaving a religion. It is also different from blasphemy, which involves disrespectful actions toward sacred things.

Many different faiths use this term in their own ways. This includes Judaism, Christianity, and Islam.

Portrait of Martin Luther as an Augustinian Monk
Portrait of Martin Luther as an Augustinian Monk

In Christianity, some thinkers called correct teaching "sound" to show it was strong. They felt heresy could be a corrupting influence. In the 2nd century, a man named Irenaeus used the term to describe his opponents. He called the main group's beliefs "orthodox." This word means "straight" or "correct" belief. People who study heresy are called heresiologists.

History shows that these disagreements often led to serious consequences. In the past, some groups faced excommunication or even the death penalty.

Supplice des Amauriciens
Supplice des Amauriciens

In the Roman Empire, Emperor Constantine the Great called a council to end a debate started by Arius. Later, the Edict of Thessalonica in AD 380 made Christianity the state church. This meant the state and the church began to work together on laws. In AD 386, a man named Priscillian was executed by Roman officials. This was one of the first times a Christian heretic was put to death by the state.

Many famous people were involved in these religious debates.

Saint Nicholas of Myra slapping Arius at the Council of Nicaea Greek Icon
Saint Nicholas of Myra slapping Arius at the Council of Nicaea Greek Icon

Martin Luther was a German friar who was excommunicated in 1520. The scientist Galileo Galilei was also brought before the Inquisition. He believed the Sun was at the center of the universe. The leaders thought this went against Holy Scripture. He had to say his opinions were wrong and lived under house arrest. Other groups, like the Cathars, were also part of large movements that the Church tried to stop.

Today, the way people talk about these ideas has changed.

Massacre of the Vaudois of Merindol
Massacre of the Vaudois of Merindol

In modern times, formal charges of heresy are much less common. Some Protestant churches still discuss the nature of God or how to read the Bible. In the Catholic Church, leaders might criticize writings for errors without using the word "heresy." For example, Pope Benedict XVI once used the term "ecclesial communities" for some Protestant groups. This was to show they lacked certain elements of an apostolic church. We can still see how these old ideas shaped the world we live in today.

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File:Saint Nicholas of Myra slapping Arius at the Council of Nicaea Greek Icon.jpg
Saint Nicholas of Myra slapping Arius at...
File:Portrait of Martin Luther as an Augustinian Monk.jpg
Portrait of Martin Luther as an...
File:Supplice des Amauriciens.jpg
Supplice des Amauriciens.jpg
File:Massacre of the Vaudois of Merindol.jpg
Massacre of the Vaudois of Merindol.jpg
File:Galileo facing the Roman Inquisition.jpg
Galileo facing the Roman Inquisition.jpg
File:Jensky kodex Zizka.jpg
Jensky kodex Zizka.jpg
File:Maker_unknown,_Sino-Tibetan_-_Acarya_Bhavaviveka_Converts_a_Nonbeliever_to_Buddhism_-_Google_Art_Project.jpg
Maker_unknown,_Sino-Tibetan_-_Acarya_Bhava...
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