Social: Verse 15 tells us that Noah supported his government by removing all of Zeniff’s people and replacing them with his own people. This is not an unusual tactic, but it helps to understand why it happens. While some of this process certainly has to do with personalities, it often has to do with the elimination of conflicts between the ways of the old regime and the ways of the new. In this particular case, it is very clear that there were new ways introduced by Noah. The new ways were so significantly different that they were sure to cause dissonance with those who represented the older way. Thus the elimination of Zeniff’s priests was a logical step for Noah.
Understanding that the removal of political adversaries has a universal logic to it, why the priests in particular? First, we must continue to remember that the modern separation between church and state did not exist in the ancient world. From what we learn of the trial of Abinadi, the priests appear to function as high political counselors as well as their religious function. Regardless of their political positions, however, the priests were also the keepers of the religious rites. It is precisely in those religious practices that Mormon sees the huge shift from Zeniff to Noah. Since the alternations in practice were religious, it was particularly imperative that Noah remove those who could have voiced religious misgivings about the new practices, and done so from respected seats of power. In order to effect his changes, Noah had to remove the old set of priests.
The next important question is where the ideas for those changes came from, particularly the institution of polygyny (more than one wife). The culture of the Nephites should have been decidedly monogamous, as polygyny was forbidden them from the time of Lehi (Jacob 3:5). Nevertheless, the Nephites in this particular area appear to have a hard time living the law of monogamy, and twice now have welcomed polygyny (those against whom Jacob contended and the current Noahites). Notice that in both cases the “whoredoms” included wives and concubines – and probably other sexual unions.
As was noted for Jacob’s time, one of the prerequisites for polygyny is the ability to support it. Multiple wives are more expensive than one wife. It is no wonder that most of the time the sins of wealth and polygyny go together. Wealth provides the economic platform that allows polygyny.
Apart from economics, however, we are still left with the problem of acceptance. The United States in modern days is a reasonable example of attitudes toward marriage. Even with Mormon polygamy in the background (and non-LDS polygamy in the underground) there is a very strong cultural bias against polygyny. It is reasonable to assume that the women of Zeniff’s city might have had a similar belief if they were surrounded by monogamist cultures. However, if the Lamanites that the Zeniffites had to do business with to gain wealth were also polygamist, then there was not only a model for such a social behavior, but a model attached to riches and prestige.
Again the parallel to Jacob’s time is instructive. The accumulation of wealth in ancient societies typically depended upon the ability to exchange goods outside the community so that one might obtain items considered rare and therefore valuable. Consider the items that are taxed to provide the living for Noah and his court. While foodstuffs are included, the rest of the valuables are workable metals. What would Noah do with the workable metals? They increased his wealth, but how?
The only way that the metals would increase Noah’s wealth – say to purchase fine clothing, would be to exchange them outside the community. If he were to exchange them within the community, what value would they have? He could never trade the metal back to those who had been taxed for the metal, because to them it would not have relative value. Noah’s wealth came from trading outside the community, and he apparently also traded in ideas, adopting concepts such as polygyny from the communities with which he traded.