how do you describe fanaticism?

I would say fanaticism is closed to what we call extremist. Anything that go extreme usually have highly negative effect especially of those things that we cannot see by our own eyes. As this world always be in balance the Ying and Yang repeat itself over and over again. There is day and night, rain and sunny days, water and fire, everything seems need to be in balance. The natures rule never defy the fact ;)

I think it's an act of commercing the religion. It gave bad influence for those who realize it. Beware, they have "smart" guy who was ready to "hypnotize" you to enter their religion unconditionally. More people join, means more donations. What a world. Getting messy every day. The spiritual identity is fading right now.

Too much on anything is not good, i think.

I would definitely say being a fanatic is negative. Fanatics think everything their religion says is 100% right and they think anyone not following it is 100% wrong. Fanatics ruin religions b/c they make the entire religion look bad! A real religious person knows how to follow their own religion and still respect others beliefs.

Fanatics are totally negative because they will go out and hurt other people for things they believe should be done. Lots of times, people are actually killed, or businesses are blown up or whatever. Religions should get their followers to stop being so destructive because it only makes their religion look really bad to the majority of people.