Why?
Read some history, if you can read.
I've read some history. And pretty much every time "God" tells people to kill others, the results are bloody and disastrous. Inquisitions, crusades, witch trials, and jihads. Yeah, that's a great track record. Years later with the benefit of hindsight we shake our heads at their mindless barbarism.
It's the age old lie, told again and again. Some opportunistic charlatan fools the masses into thinking God whispers into his ear. And quite by coincidence of course, God just happens to want leaders to do things that benefit their own power and prestige.
Fool me once shame on you. Fool me twice shame on me. Fool me a hundred times and I need to have my head examined.