A big title for a small subject really, but it's a recurring thought I've had on and off for the past couple of years and I haven't seen mention of it elsewhere. So, to get it out of my head (and scavenge a last-minute opportunity before Halo 3's release to appear to be a seer of tru7h) I'll scribble it down here.
Why, specifically, do Covenant creatures refer to the Chief as "Demon" or "Devil"? What part of their dogma led to this? Was it the Prophets labelling Humanity's greatest defenders as unwholesome abominations?