I'm gonna ignore your question and answer my own one which arised from the title.
Societies that are religious can effectively ensure everyone in the society is following rules, and reproduces. Religion and fear in God polices people to behave in ways beneficial to the society, and this is what 99% of the Bible points towards. For example, the 7 deadly sins are coincidentally the 7 things that ruin relationships / business partnerships / families. Societies that use religion come out as more stable, they tend to grow in numbers, and are therefore stronger.
So belief in God is a consequence of the evolution of society. Religious societies tended to survive more than atheistic ones, and hence conquer most of the Earth.
Another theory is that there is a "God Gene" in people, which is a consequence of evolution of genetics. The idea is, a belief in God forces a person to a) generally act more responsibly in a group and thus ensure it's survival and b) believe his life has a meaning, and therefore not kill himself out of existentialism.
But should you believe in God's actual existence? Only if you're retarded. Once you see that it is (a very respectable) trick to change people behaviour, you open a pandora's box you cannot close and undo your enlightenment. No wonder atheists were killed before they could spread their heresy and make society collapse.