There's really no such thing as the agony of dying. I'm quite sure that pain is shut off at the moment of death. You see something happens when the body knows it's about to go. Peptide hormones are released by cells in the hypothalamus and pituitary gland. Endorphins. They attach themselves to the cells responsible for feeling pain.
It is commonly said and known that each civilization has its own religion. Now my claim is that if we look deeper the different civilizations were brought into being by the different revelations.