I would say it is unwise to do anything else. However, I would hardly suggest anyone go around telling people that they intend to kill someone. That will only make people afraid of you but not necessarily make any potential assailant refrain from doing you harm. My father said that the person who is afraid of you is the person who will kill you. But if you have a Christian philosophy, all of this is a moot question. Not because you wouldn't defend yourself but because you do not have anything worth stealing. In any event, most notions of self-defense involve a degree of paranoia, which is a form of vanity. Mind you, I am saying this as an old man. Others will have their own point of view.