Again the Nephites were victorious, and again they boasted in their own strength (vv. 8–9). Their swearing by the heavens and the throne of God (v. 10) was a direct contradiction to what Christ had taught as the higher law during his ministry among them and in Jerusalem (see 3 Nephi 12:34–35; Matthew 5:34–35). Furthermore, the Nephites were threatening to fight an offensive war. The law of war justified them in defending “your families even unto bloodshed” (Alma 43:47), but they “were also taught never to give an offense, yea, and never to raise the sword except it were against an enemy, except it were to preserve their lives” (Alma 48:14). When they lived by this law they had been successful (see 3 Nephi 3:20–21), and when they didn’t they were defeated (see Mormon 4:4). Thus, Mormon’s refusal to lead them (Mormon 3:11) was in accordance with the law of war. He had done everything that was humanly possible, and had sought the help of God in their behalf (v. 12).
Again regarding the law of war that the Lord had given unto his ancients, “if any nation, tongue, or people should proclaim war against them, they should first lift a standard of peace unto that people” three times, and then should “bring these testimonies before the Lord.” Then he “would give unto them a commandment, and justify them in going out to battle against that nation, tongue, or people. And I the Lord would fight their battles, and their children’s battles” (D&C 98:33–37). Mormon had led them three times out of the hands of their enemies (Mormon 3:13). The first time was in A.D. 330 (see Mormon 2:9). The second time was in A.D. 346 (see Mormon 2:22–26). The third time was in A.D. 361 (Mormon 3:7 above). Therefore, the effect of raising the standard of liberty to an enemy had been shown to the Nephites, although in a somewhat different way. It is usually shown to the enemy, and perhaps it was, but the Nephites knew they had been blessed in being able to be victorious. After their fourth victory (v. 8), they had apparently willfully sworn the oath of revenge, and Mormon had brought his testimony (vv. 11–13) before the Lord against them. The Lord had fought their battles, and the Nephites had rejected him. The voice of the Lord came to Mormon in accordance with the law of war. Vengeance is his and he would repay. Because the Nephites had not repented, and had intentionally and knowingly rejected him four times, they would be destroyed (v. 15; see also D&C 98:44).