By now the complaining of Nephi's brothers is no surprise. The part of this verse that provides more insight into the dynamics of the family is the attempt at a work boycott by the brothers. Perhaps they were simply protesting working on something so difficult after their arduous journey, but Nephi is at least personally clear that their attempt to refuse to work came directly as a protest to Nephi's leadership.
Laman and Lemuel are denying the authority of Nephi to require their labor, and they deny it on the unstated (but in no need of stating) incongruity of a younger brother commanding his elder brothers as well as the important denial of deity-favored status for their younger brother. In order to continue to maintain their opposition to Nephi's assumption of leadership over them, they must deny his direction from the Lord to do so.