Although this is a very quick statement, it is very important for the way Mormon develops his theological and historical story from this point forward. He has begun pointing his readers to the potential problems in the north, even though the Lamanites in the south continue to be the cause of the periodic wars. In this verse we have two important statements. The first is that there arose contention and dissension. That has happened before, but in previous times the dissenters went south to the Lamanites. When the dissenters went south, they stirred up trouble.
The second statement is that these dissenters go north. Mormon implies that these northbound dissenters also stir up trouble, but the true trouble is manifest only gradually. The real indication of how important Mormon’s statement of dissenters going north will become in his text is indicated by the amount of space that he allots in the next few verses (4–16) discussing what he knows, or what he is interested in pointing out, about where they went. When he is finished inserting this that somewhat off-topic information, he repeats that he is dealing with the forty-sixth year (see verse 17 of this chapter), a repetitive resumption that he uses in order to return to a story that he will interrupt beginning, in the next verse.