The epistle ends with the writer’s official declaration of identity and title. As part of that declaration, he states the antiquity of his authority. The Nephites have an authority that rests on one kind of antiquity, but the Gadiantons trace their ruling authority to an even older source, the Jaredites. This connection will become even more important, not only at this period but also in Mormon’s time. (See Helaman, Part 1: Context, Chapter 3, “The Gadianton Robbers in Mormon’s Theological History: Their Structural Role and Plausible Identification.”)
The final clause provides further evidence for the hypothesis that many current Gadiantons had previously ruled in Zarahemla. Giddianhi can confidently assume that Zarahemla still holds many sympathizers and that victory will be assured in an all-out battle. He justifies this war of destruction by citing unspecified wrongs committed against former rulers, whose “rights of government” were stripped from them. (See commentary accompanying v. 4.)