To be reverent is much more than just to be quiet in church. It is to show love for Heavenly Father and Jesus Christ by appreciating all that They have done for us. It is to willingly do those things that They have asked us to do. It is to honor and respect Them and all that They created, including ourselves.
Moroni, the son of Mormon, was reverent. But after his father died in battle, he was the only one who was reverent. All around him were people, both Nephites and Lamanites, who did not love Heavenly Father and Jesus Christ. These people had forgotten what wonderful things had been done for them—even the visit of the Savior to them after His death. Instead, both the Lamanites and the Nephites disobeyed the commandments, and they hated each other and killed each other.
They would have killed Moroni, too, if they could have found him. But he hid from them and finished writing his father’s teachings on the sacred records. He also wrote of the final destruction of his people, the Nephites, testified of Christ and Heavenly Father and the plan of salvation, and taught us about such things as church meetings and the sacrament and how we should treat one another.
Despite all the hatred around him, Moroni did not hate the Lamanites or the Nephites who had become so wicked, so irreverent. He felt extreme sorrow for them and sealed up the plates so that future Lamanites—and we—can learn of the greatness of God and be reverent, as Moroni himself was.