From this passage we learn that human relationships are fragile. One day you are fighting side by side, putting your life in the hands of your fellow tribesman, the next you prepare to kill him. From friends to enemies in the blink of an eye. That is the sad reality of the human condition. Given our sinful natures, conflict can come at any time and so we must be ready to face it.
1 Alors Josué appela les Rubénites, les Gadites et la demi-tribu de Manassé.