Mormon confirms how dangerous Amalickiah is. Although Mormon is taking the story from the large plates, these two verses see Mormon explaining why he selected this story to tell. There is a moral at play here, and Mormon wants his readers to clearly see that moral. Thus, Mormon warns his future readers specifically about Amalickiah, but also against all who might be, as Amalickiah was: “a man of cunning device and a man of many flattering words.”
When Mormon tells us that Amalickiah sought “to destroy the foundation of liberty which God had granted them,” it was a warning that Amalickiah was leading the people away from God. By leading them away from God, he was leading them away from the protective covenant of the land.