The final verse in Abinadi’s declaration is, "The Lord had made bare his holy arm" (30). Noah and his priests might have thought of this baring or manifesting of the holy arm of the Lord as the way in which they had won all their victories. But Abinadi declared that the way in which God will make bare his holy arm is through the salvific labor of his right hand man, namely his Son, who will be seen in the eyes of all nations.
All of this explanation began, back in Mosiah 12:21–24, when the priests had asked, at the end of their quotation, what does it mean to "make bare his arm in the eyes of all nations, and all the ends of the earth shall see the salvation of our God." In Mosiah 15:22–28, Abinadi ended his extended testimony by concluding: "I say unto you that the time shall come that the salvation of the Lord shall be declared to every nation, kindred, tongue and people, and people shall see [God] eye to eye and shall confess before God that his judgments are just" (Mosiah 16:1), referring to the message of the gospel of Jesus Christ that will be delivered to all and the final judgment that will then justly confront all mankind.
With all of that, Abinadi not only successfully rebutted the accusation of the priests that he had prophesied falsely, but he implicitly counterclaimed against them of their own wickedness, for "then shall the wicked be cast out, … they [who are] are carnal and devilish, … and persist in the ways of sin" (16:2, 3, 5).