The sons of Mosiah - Ammon, Aaron, Omner and Himni - left Zarahemla (about 90 B.C.) with the sole purpose of preaching the gospel to the Lamanites. Once they reached the borders of the land of Nephi, where the Lamanites dwelt, they went their separate ways.

Ammon went to the land of Ishmael, where he successfully taught the gospel to Lamoni, king of that part of the Lamanite lands, and established branches of the Church. (See Church News, May 21.)Few details are given of where Omner and Himni went individually during their labors among the Lamanites. Most references to them are made in conjunction with the labors of the four sons of Mosiah as a group.

More is known of Aaron and his labors. He went to the land or city of Jerusalem, which the Lamanites named after Jerusalem in Judea. This New World Jerusalem was near the water of Morman (Alma 21:2), where approximately 55 years earlier (145 B.C.) Alma the elder had baptized "about two hundred and four souls." (Mosiah 18:16.)

Two groups had helped the Lamanites build this newer Jerusalem: the Amalekites and the Amulonites.

The origin of the Amalekites is not made clear in the Book of Mormon. Apparently, they were a sect of Nephite apostates who, some years earlier, had affiliated with the Lamanites.

The Amulonites were descendents and followers of Amulon, a wicked priest of Noah, the apostate Nephite king who killed Abinadi. (Mosiah 17:20.)

Alma 21:3 gives a brief, yet powerful, description of the people in the Jerusalem that Aaron approached.

"Now the Lamanites of themselves were sufficiently hardened, but the Amalekites and the Amulonites were still harder; therefore they did cause the Lamanites that they should harden their hearts, that they should wax strong in wickedness and their abominations."

In Commentary on the Book of Mormon, George Reynolds and Janne M. Sjodahl wrote:

"Brought up on traditions which were untrue besides being most wicked, the Lamanites . . . were in and of themselves a hard and ungracious people. But the Nephites who had become dissatisfied with their own people and had aligned themselves with the Lamanites were still harder. The venom so often seen in apostates was in them deeply infused.

"By stories of Nephite atrocities and Nephite intentions toward them, the Lamanites were goaded on to seek revenge. . . for injustices never perpetrated. Under the constant urging of the Amalekite and Amulonite apostates, the Lamanites grew more and more in the wicked intents of their hearts; the Sacred Record says, 'that they should wax strong in wickedness and their abominations.'" (Alma 21:3.)