Ammon boasted in the Lord; that is, he rejoiced or gloried in him. He knew (as every disciple knows) that he was weak and could do nothing by himself, but he also knew that in the strength of the Lord he could do all things (compare the very same message from Paul in 2 Corinthians 12:7–10.) We know, as Ammon knew, that we can do whatever is required of us “because of the power of his word which is in us.”
Consider what had happened. The Nephites and Lamanites were always warring and had an intense hatred for each other—a seemingly hopeless situation, but look how that changed. The friction between the United States and the Soviet Union was intense for decades, but look at the success beginning in the 1990s in carrying the gospel to the Russians and other peoples. The animosity and antagonism between Jews and Arabs has been even more severe for many decades. Is there anything that could heal that enmity? Yes, indeed. The Savior and his gospel can heal the deep wounds of centuries of bitter hostility.