This story is as much a story of honor as it is a story of Nephite good guys and Lamanite bad guys. Both sides approach this battle with a sense of honor that is played out in this final battle. Moroni offers surrender under certain terms. Zerahemnah cannot accept the terms, and rather than lie about his intentions, he returns to fight. When the battle becomes hopeless, Zerahemnah now accepts the terms. He is willing to make a promise now that he was not willing to make earlier.
In spite of the coerced nature of this final promise, Moroni nevertheless accepts the promise of Zerahemnah and allows the Lamanites to depart “into the wilderness.” There is no fight to destruction. There is nothing that will every allow Moroni to know whether or not Zerahemnah will keep his promise. Nevertheless, Moroni accepts the verbal treaty, and the enemy is allowed to depart. It is a story of honor of both sides.