As a result of conversion, the four sons of Mosiah volunteered, and were given permission, to go south to the land of Nephi, where Zeniff, Noah, Limhi and Alma had been (28:8). They desired to help people on all sides to be "friendly to one another, and that there should be no more contentions in all the land" (28:2).
Why do you think the sons of Mosiah would have taken the love they had felt and said, "God, I love you so much, I will go to the Lamanites and teach them?" How would that be an expression of that love? For one thing, these Lamanite outsiders were, after all, still relatives—distant relatives, yet still part of the family of Lehi. There was a big concern about preaching to the Lamanites. No doubt they wanted to undo some of the hostility that existed between the Nephites and the Lamanites and to solve long-standing problems.
There was a bit of a political motive behind this too. The land that the Lamanites possessed was a special land to many people in Zarahemla because it was the land of the first of inheritance, part of the land of promise. Alma’s father had grown up there, and of course that had been a very important part of what Zeniff, Noah, Limhi, and those people had thought they were doing. Alma had grown up as well with the people that had come from the land of Nephi with Limhi. He may have known them for as many as 20–25 years. There was a whole community of people who had come from there, so they knew something of that land. That may have sparked some of their interest in wanting to go back and preach the gospel there.
One wonders why they did not come home after a few years, rather than staying there for 14 years. The religious motivations were the impetus that took them through this long, difficult mission. Apart from the success of the work, their absence from Zarahemla may have had something to do with the political environment back at home. All four of Mosiah’s sons went. They didn’t trade off, where some of them could have gone for a period of time while others stayed to take care of the kingdom. Instead, all four chose to go, partly because they knew that as the heirs-apparent there would be people in the city of Zarahemla that would want them to be king if they were around.
When Zeniff had gone back up to the lands of the Lamanites, he didn’t go with a missionary attitude. Instead, he went with a colonization attitude, and there was hostility that only made things worse. Maybe the Nephites had learned a lesson from the experience of the people of Zeniff. The sons of Mosiah may have wanted to go back and try to do some international diplomacy the way the Lord would have liked it to be done. Of course, Ammon, the prince, the heir apparent, ended up being a slave. He was not going in order to conquer these people. The approach was completely different as a result of this conversion. This event was fundamentally paradigm-shifting for everything. They were now thinking in a completely different way.
In the fifth year of the reign of judges, in Alma chapters 2 and 3, in the new kingless system, there was a civil war in Zarahemla led by a man named Amlici. He wanted to be king. He wanted to reinstate the kings. There must have been a very substantial, political group in Zarahemla that liked the old system.
There were plenty of good, religious reasons for the sons of Mosiah to go, but there is also the issue that the Lord wisely kept them away from these difficulties. These four sons were smart enough to realize that if they stayed around, they were going to be in the crossfire. Transitions of political power were always a problem for the Nephites, as for most civilizations. On another occasion, when we get to the end of the book of Alma and the beginning of the book of Helaman, there were three brothers in Zarahemla. One was named Paanchi, another was Pahoran, and the third was Pacumeni. Within one year, all three of them were dead because there were factions with different political people supporting them. As the power shifted, they were caught in the middle of this and they did not survive. We see that these types of things really can and did happen. The situation that the sons of Mosiah were in could have gone very badly. But it worked out wonderfully in the end because they did the right things for the right reasons, and followed the inspiration of the Lord.