Mosiah 29:1 - 29:5

Mosiah 29:1 Now when Mosiah had done this he sent out throughout all the land, among all the people, desiring to know their will concerning who should be their king.

After Mosiah had given the records to Alma, he sent a letter to all his subjects asking them who they wanted as their king to replace him at his death.

Mosiah 29:2 And it came to pass that the voice of the people came, saying: We are desirous that Aaron thy son should be our king and our ruler.

They responded by choosing Aaron.

Mosiah 29:3 Now Aaron had gone up to the land of Nephi, therefore the king could not confer the kingdom upon him; neither would Aaron take upon him the kingdom; neither were any of the sons of Mosiah willing to take upon them the kingdom.

Aaron had gone to the land of Nephi with his brothers to preach the gospel to the Lamanites. Aaron must had indicated to his father that he did not want the kingship anyway before he left. The other brothers also refused to be the king.

Mosiah 29:4 Therefore king Mosiah sent again among the people; yea, even a written word sent he among the people. And these were the words that were written, saying:

So with no sons to confer the kingdom on, he thought that it was now time to consider another approach how to rule the Nephites. After some thought, he sent another letter to them outlining his ideas on another form of government.
[I’m sure his new approach did not come up just then. I’m sure he was thinking about this for a long time and maybe even before his boys turned down being king. He may have thought that being king was to much responsibility for one man and wanted some other form of government to be in place instead of a king. He must have also studied the scriptures looking for some guidance in this manner. I’m sure the Lord was inspiring him as well.]

Mosiah 29:5 Behold, O ye my people, or my brethren, for I esteem you as such, I desire that ye should consider the cause which ye are called to consider—for ye are desirous to have a king.

He begins by calling all the people his brothers and sisters. He does not consider himself any better than any of them. But he says it is now time to think hard on the crisis they now face of picking a replacement for him as king. This is a major decision that will effect all the people for years to come.