First, consult an attorney. This will cost some money, but you would have a heckuva time spending the money if you are dead. Then, go to court and get a court order for him to leave your house and stay away from you and your family. The threats should be enough to convince a court to issue an order to leave your house and stay away from you and your family. Be prepared to deal with any fallout, like your wife defending him.
With a court order, the police can intervene, where they might not in a purely domestic matter. If he violates the order, then the police can (and hopefully will) enforce the court order, where they probably won't take action on just your say-so. In addition, if you have to take drastic action, the court order shows you tried to deal with the issue in a legal and non-violent matter, and it was his actions that led to the large hole in his head.
Jim