User blog comment:General MGD 109/Who's the strongest demon/@comment-213.205.233.124-20130721221628

Azazel said that the colt was the only weapon that could kill him. Plus he gave sam his powers, so odds are he would be immune to them. He is also the reason that sam is immune ti lilith. Not to mention that he doesnt appear to be afraid of angels when he is in Samuel (marys dad).