Why is there so much fighting between religious groups?

All humans have disputes on numerous topics. The reason that religious groups fight so much is because they strongly believe in their religions, do not want others to have different beliefs/ spread their "wrong" beliefs, and are wiling to fight for their own beliefs. Religion is a highly important part of every culture, and often times is a very important (if not most important) part of people's lives. It is only natural to stand up for what you believe in- unfortunately, some religious groups decide to show their dedication by fighting. In some religions, fighting "holy wars" against those who do not share your beliefs is an obligation and honor.

In sum, religious groups do not accept others' beliefs and show their disagreement by fighting.