I can't say who first presented it, but I would wager that the reason was to frighten people into behaving themselves.
There's certainly no evidence for it. But you can never prove a negative, so the best we can say is, probably not.Does hell exist?
I certainly don't need it, but if that's all that keeps someone from going out and raping or killing people, then by all means let them keep believing.Does there have to be a hell to make us behave?
Good behavior is treating others with the same courtesy and respect with which you would like to be treated.What is good behaviour?
Again, I don't think hell has anything to do with it. We should fight injustice regardless. "All that is necessary for the triumph of evil is that good men do nothing." (Edmund Burke)What role does the concept of hell or no hell play in our being capeable of living with injustice in this life?