Because of a certain level of tension between the two religions, Muslims and Christians are often met with hostility in communities dominated by the other.
Members of the religious mainstream usually disapprove of fanaticism, but some also feel it to be necessary to maintain cultural identity and spread the perceived word of God.
Fanaticism, from French fanatique or Latin fanaticus 'of a temple, inspired by a god' is an emotion of being filled with excessive, uncritical zeal, particularly for an extreme religious or political cause, or with an obsessive enthusiasm for a pastime or hobby.
The difference between a fan and a fanatic is that while both have an overwhelming liking or interest in a given subject, behaviour of a fanatic will be viewed as violating prevailing social norms, while that of a fan will not violate those norms (although is usually considered unusual).(ThorneandBruner 2006)
religiousfanaticism - the most extreme form of religious fundamentalism, which typical takes on violent, and potentially deadly dimensions