Fanaticism

[Sarah]

Excessive enthusiasm, unreasoning zeal, or wild and extravagantnotions, on any subject, especially religion; religious frenzy.

[Sarah]

Obsessive devotion combined with thoroughly invasive attempts to convert people to whatever is being devoted to.

Devotion alone is not harmful. Teaching people about one's devotions or beliefs isn't harmful.

But people are completely out-of-line when they force people into unwilling bondage with the threat of death.

Usually, fanaticism is driven by power-hunger, corruption given by power, the strong desire to be considered right, misinterpretation of religious texts or other manifestos and documents, and/or insanity.

It's not often monetarily driven. That problem is usually called greed, an obsession with money. (Which I suppose might be a type of fanaticism.)

[PussyCat]

extreme beliefs that may lead to unreasonable or violent behaviour:

[Sommer]

The quality of being fanatical.