Fuck it, Imma copy and pastin' this. I don't feel like writing it a second time--and because I think I said what I needed to say already anyway. So here goes.
...and you worship this--entity--exactly WHY again?
Is it out of fear? It can't be out of love, surely. It really isn't possible to love anyone ready, willing and eager to murder or torture you at the drop of a hat. Are you simply terrified that this is what he'll do to you if you DON'T? Do you hope that he'll remove whatever remains of your humanity when you die so that you're no longer capable of fear or empathy or pain? Or, whatever God exists help you, do you actually WANT to be transformed into a creature that finds the brutal torture of other people to be amusing and enjoyable?
Or is that what you are NOW?
If this is REALITY--that is, if there IS a God and an afterlife, you're right about his nature and his character and THIS is what he's like--then telling other people about it isn't a kindness to them. Imparting to them the certain knowledge that this is what's going to happen to them for all eternity, that the only way to avoid it is to endlessly supplicate themselves in terror to the Demiurge in the hopes that, when they die, they'll be taken to Its side where they'll be forced to WATCH endless brutality and horror for eternity until they finally lose their remaining humanity isn't doing them any favors.
The only kindness possible in that scenario is not telling them. Let them live their lives in whatever momentary illusion of peace they can find. They'll have all eternity to find out what **reality** really is without you poisoning whatever time they have remaining with the knowledge of the horror that awaits. Nothing they, or you, could possibly do after death can matter, because nothing we can do can change anything for the better. Let them live their lives. Tell them a happy lie or say nothing, because that's the ONLY ethical choice you, as a believer in this scenario, can make.