Religion serves a number of purposes:

1) control the masses - best done with incomprehensible rites and texts that must be explained by leaders

2) a system that answers the common mans Why? - doesnt need to make sense, but works best if the narrative is simple and unwavering, e.g. God chose to do it that way and His ways are inscrutable.

3) eternal punishment for the evil and blasphemous - Karmic? Probably not the correct definition but something very similar.

The rulers very much like to use #1. People in general do ask Why? And people seem to be born with a (self-centered) sense of justice.

Which all goes a long way toward explaining the staying power of religion.

How eager they are to be slaves - Tiberius Caesar

Coulda tripped out easy, but I've changed my ways - Donovan