I'm probably going to be harmed for this.

A long while ago me and my family had a conversation in jest. "What would happen if God decided to make soup?" My parents asked me without explaining much, this is by the way one of my first memories since I could walk around. I replied "Devils would put bad ingredients in the soup to ruin it, but they'd be caught by Angels, which would put good ingredients to counter it; their own ingredients." My father asked me after "What would the soup be like when God tries it?" I replied "I think the soup would neither be good nor bad, it would have both good and bad things." I added "It depends on which combination he scoops, meaning if he had a potato and an onion in one spoonful he might like it more than if he had a carrot and an onion slice."

Anyway they were talking about the primordial soup, and I just gave you a more realistic theory on to how we were formed than what religious books say.

Of course Devils aren't all bad and Angels aren't all good so this is subjective.