These verses originally followed immediately upon Mormon’s lamentation for the destruction of his people. He had just stated of his current destroyed people: “O that ye had repented before this great destruction had come upon you” (Mormon 6:22). Now he transitions from the sadness of what cannot be recovered to a future remnant of that destroyed people who will still be capable of restoration to the house of Israel.
Therefore, as Mormon begins, he speaks to his future audience. Although he has previously known that his future audience would include the Gentiles, he is speaking particularly of the remnant of his people. They are the ones who are on his mind in these final days. This will be the last time that Mormon writes on the plates. After this, Moroni takes over. Thus, this chapter gives us Mormon’s final thoughts on the work he has produced.
What should that future remnant know? That they are descendants and inheritors of the blessings of the house of Israel. That they must repent. That they must come to the knowledge of their fathers (through Mormon’s writing), and that this will lead them to “believe in Jesus Christ, that he is the Son of God.”
Very interesting is that they “must lay down [their] weapons of war.” That aspect of repentance has been used to show what happened when the Lamanites became righteous. Most readers of the Book of Mormon remember the Anti-Nephi-Lehies who laid down their weapons of war, and we see that again in Helaman 5:50–51.