Religious fanatic

Religious fanaticism is uncritical zeal or with an obsessive enthusiasm related to one's own, or one's group's, devotion to a religion – a form of human fanaticism which could otherwise be expressed in one's other involvements and participation, including employment, role, and partisan affinities.

Steffen gives several features associated with religious fanaticism or extremism:

Ever since Christianity was established, some of those in authority have sought to expand and control the church, often through the fanatical use of force. Grant Shafer says, "Jesus of Nazareth is best known as a preacher of nonviolence. The start of Christian fanatic rule came with the Roman Emperor Constantine I as Catholicism. Ellens says, "When Christianity came to power in the empire of Constantine, it proceeded almost to viciously repress all non-Christians and all Christians who did not line up with official Orthodox ideology, policy, and practice". An example of Christians who didn't line up with Orthodox ideology is the Donatists, who "refused to accept repentant clergy who had formerly given way to apostasy when persecuted". Fanatic Christian activity, as Catholicism, continued into the Middle Ages with the Crusades. These wars were attempts by the Catholics, sanctioned by the Pope, to reclaim the Holy Land from the Muslims. However many Catholics see the crusades as a just war in self-defense. Charles Selengut, in his book Sacred Fury: Understanding Religious Violence, said:

The Crusades were very much holy wars waged to maintain Christianity's theological and social control. On their way to conquering the Holy Land from the Muslims by force of arms, the crusaders destroyed dozens of Jewish communities and killed thousands because the Jews would not accept the Christian faith. Jews had to be killed in the religious campaign because their very existence challenged the sole truth espoused by the Christian Church.

Shafer adds that, "When the crusaders captured Jerusalem in 1099, they killed Muslims, Jews, and native Christians indiscriminately". Another prominent form of fanaticism according to some came a few centuries later with the Spanish Inquisition. The Inquisition was the monarchy's way of making sure their people stayed within Catholic Christianity. Selengut said, "The inquisitions were attempts at self-protection and targeted primarily "internal enemies" of the church". The driving force of the Inquisition was the Inquisitors, who were responsible for spreading the truth of Christianity. Selengut continues, saying:

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