Religion is based on fear – and feeds off it. Einstein maintained that the idea of a God that protects, punishes, and rewards man arose from the fears of primitive societies. The world was too vast and daunting, and they needed assurance that there was someone watching over them. And for this to work, they needed other people to buy into it. That’s where the ideas of heaven and hell emerged: if the promise of eternal pleasure did not bind people to God, then the fear of eternal suffering would. And this works, a bit too effectively.