Reading through this thread, I see some great posts. I have a lot if views on this subject, and will list a few of them here.
Religion is a way to explain the natural world in the absence of scientific evidence. People are prone to assign intent to random observations, and this is related to the dopamine levels in your brain.
http://aeon.co/magazine/psychology/dopamine-marks-the-line-between-religious-believer-and-fanatic/
There is a lot in the literature on this, but I cannot post it due to copywrite law.
The Druids believed in the power of the trees, the Native Americans had many guiding/controlling spirits that ruled nature. The Romans and Greeks had their myths. A few thousand years ago there was a shift to monotheism, which really isn't unless 3=1, but that's a different argument all together. Every culture had its creation myths. Here is 10 of them to look at:
http://listverse.com/2014/01/11/10-creation-myths-as-strange-as-the-bible/
Here are a few others that are very similar to Christianity:
http://listverse.com/2009/04/13/10-christ-like-figures-who-pre-date-jesus/
These are based on the hero archetype:
http://www.rationalskepticism.org/general-faith/lord-raglan-on-mythic-heroes-t2089.html
So, when you look at the evolution of spiritual beliefs, they follow a pattern that has evolved to be relevant to the culture, as people moved from hunter gatherer to agrarian, then industrialized societies. In this day, religion is becoming much less relevant to cultural norms. Numerous examples exist, such as climate change, human rights, equality of women, overpopulation, and many others. Solutions are opposed by people who fundamentally believe in a book that is millenia old, and no longer relevant. Additionally, people of the three major religions continue killing each other because the God of Abraham promised the world to three groups of people. Yes, that is correct, Christianity, Islam , and Judaism are all based on the same god, and share a number of books in their holy tomes.
Science only shares one principle with religion. It tries to explain the natural world, but in every way other than this it is different. Science looks for evidence and proof. It requires metagognition, rather than faith. It gives statistical probabilities. The results are accepted, even if the hypothesis is not supported. One does not have to explain away science, and if new evidence makes previous "truths" obsolete, it accepts that and evolves. This is not proof of the fallability of science, it is the quest to find the best explanation we can based on the evidence we have.
One of my issues with religion is the homocentrism of it all. The entire expanse of this vast universe was supposedly created for us. We can only observe about 1/1000 of it as our best guess, and we can only perceive through senses that make the majority of the universe unobservable to us. What a cruel trick to play on the reason for the universe.
When human suffering can be diminished through science, and religious groups block that because of an interpretation of a myth written two millenia ago (give or take several centuries) it is obvious that there will be conflict. I'm trying to stay away from politics here, as I understand that is against the rules, so I'm leaving it as the goals of religious groups versus scientific groups on issues that can benefit humanity, regardless of political systems.