Although Mormon does not signal when he departs from a source that was not the large plates, he does tend to signal a return to a separate source. In this case, it is either the return to Alma’s record, or simply to the reiteration that the significant information is coming from Alma’s personal record that is important.
As with the previous sermon, this one will be quoted from Alma’s record. Although it is obvious that Alma recorded the sermons on separate records, it is not clear how much linking material he provided. If it was his personal record, there might not have been much, as he knew what it was, and perhaps he was not writing to inform a specific future audience of those events.
What we can tell is that Mormon provides the rather generic linking material between the quoted sermons. Since the linking material was wholly contained in the short Chapter 6, Mormon begins this chapter with the quoted material and no further narrative introduction.