Alma 44:6 - 44:10
Alma 44: 6 Yea, and this is not all; I command you by all the desires which ye have for life, that ye deliver up your weapons of war unto us, and we will seek not your blood, but we will spare your lives, if ye will go your way and come not again to war against us.
Moroni demands, in addition, that the Lamanites give up their weapons and covenant that they will not come against the Nephites again. If they Lamanites will make this deal, the Nephites will not kill them and they can return home.
Alma 44: 7 And now, if ye do not this, behold, ye are in our hands, and I will command my men that they shall fall upon you, and inflict the wounds of death in your bodies, that ye may become extinct; and then we will see who shall have power over this people; yea, we will see who shall be brought into bondage.
If the Lamanites will not agree to these terms, the Nephites will continue the fight until all the Lamanites are dead. That should convince everyone that the Nephites have the power to fight off anyone who thinks they can bring the Nephites under subjection.
Alma 44: 8 And now it came to pass that when Zerahemnah had heard these sayings he came forth and delivered up his sword and his cimeter, and his bow into the hands of Moroni, and said unto him: Behold, here are our weapons of war; we will deliver them up unto you, but we will not suffer ourselves to take an oath unto you, which we know that we shall break, and also our children; but take our weapons of war, and suffer that we may depart into the wilderness; otherwise we will retain our swords, and we will perish or conquer.
Zerahemnah comes forth to Moroni to surrender his weapons of war. He said the Lamanites would give up their weapons and return home but would not make the covenant of not trying to attack the Nephites again. He said that they or their descendants would probably brake the oath anyway. If that was not good enough, then the fight would continue with either them conquering or they would die in battle.
This shows some honesty by Zerahemnah. It should be obvious that the Lamanites would eventually attacked again sometime in the future so why made a covenant that they would not keep anyway. I am guessing that Moroni was at least hoping that they would have some peace until the next generation for a few years.
Alma 44: 9 Behold, we are not of your faith; we do not believe that it is God that has delivered us into your hands; but we believe that it is your cunning that has preserved you from our swords. Behold, it is your breastplates and your shields that have preserved you.
Zerahemnah said that they were not of the faith espoused by the Nephites and did not believe that it was their faith that gave them the advantage over the Lamanites. The advantage was the Nephites body armor that made the difference.
Alma 44: 10 And now when Zerahemnah had made an end of speaking these words, Moroni returned the sword and the weapons of war, which he had received, unto Zerahemnah, saying: Behold, we will end the conflict.
With that response, Moroni gave Zerahemnah back his weapons and said that the battle will continue until the Lamanites are dead or they make the covenant.