"Be ye angry, and sin not: let not the sun go down upon your wrath:
Neither give place to the devil."
Interesting, and the Joseph Smith translation (JST) is interesting as well. The first part of the scripture is changed to "Can ye be angry, and not sin?" I think that is a remarkable question, and the whole scripture seems to be saying that, even without the JST. It seems to me to be saying that being angry is kind of like inviting the devil into your life. I find that to be true, at least in my own life. I know that when I am powerfully angry with someone, it is hard for me to pray or to feel the spirit at all. Back in the old days when I was a psychology major, I remember one of my professors telling us that anger is a secondary emotion. There is always some other emotion that happens first, and we use anger to mask it. Perhaps we are hurt or desolate... or even surprised or embarrassed, but instead of allowing ourselves to express the real emotion we revert to anger, because it is less vulnerable. It's hard to find the primary emotion, but it helps us to keep our souls out of the hands of Satan... and although it is painful at times, vulnerability is a lot better way to learn than aggression.