As this verse implies, the polygamous influences that the Nephites are adopting are not those of the tribal/lineal Lamanites. Jacob had earlier used the term collectively to mean anyone who was not a Nephite (Jacob 1:14), but he also acknowledged the existence of tribal identities: “Now the people which were not Lamanites were Nephites; nevertheless, they were called Nephites, Jacobites, Josephites, Zoramites, Lamanites, Lemuelites, and Ishmaelites” (Jacob 1:13). Only the context can clarify whether “Lamanite” is being used as a non-lineal or a lineal term, as a synonym for “non-Nephite” or as anyone directly descended from Laman. By specifying the “Lamanites our brethren,” Jacob signals that he is referring to lineal, not generic, Lamanites.
Jacob’s argument requires a close connection between his audience and the Lamanites. Therefore his meaning is strengthened when his audience understands that he is speaking of lineal Lamanites. Because Jacob is commending the Lamanites for obeying Lehi’s command, the sentence makes sense only for those descended from Lehi. This can pertain only to those who would have received that commandment. Generic Lamanites would have been under no such mandate, not recognizing Lehi as a family or spiritual leader.
Jacob contrasts the supposedly unrighteous descendants of Lehi’s sons with the supposedly righteous descendants of another. This intimate parallel depends on both the familiar connection and on the startling reversal of unrighteousness/ righteousness between the Lamanite and Nephite peoples. The Nephites assume that they are superior in all ways to these lineal Lamanites, but Jacob identifies the Nephites as morally inferior on the point in question. Jacob intends to shock the Nephites into returning to Yahweh’s way.
Jacob charges that the Nephites hate the Lamanites “because of their filthiness and the cursing which hath come upon their skins.” This description matches Nephi’s description of what happened to the Lamanites after the split between the two peoples (2 Ne. 5:21). Jacob, however, uses “hate” as a literary synonym for unrighteousness. In Jacob’s sets of parallels, he must contrast extremes. The Nephites certainly consider themselves as righteous, yet Jacob dismisses as a valid reason a comparison to the Lamanites’ “filthiness” and “dark skin.” The Lamanites’ “color” clearly is associated with unrighteousness—a meaning Jacob counts on to make his point. (For more information on the ascription of skin color as a metaphor, see commentary accompanying 2 Nephi 5:20.)