Textual: The structural format of this inserted citation is one that allows Alma to record not only the events of the discourse, but his reaction to them. Because this is an account being written by the protagonist, we are certain to have his viewpoint emphasized. Thus verses 2 and 3 are a paired set, with verse 2 being the contending statement, and verse 3 being Alma’s inserted commentary on the nature of that argument. Verses 4 and 5 form a similar set of point and counterpoint, even though Alma’s insertions interrupt the logical flow of the Ammonihahite contention.
The counterpoints between the Ammonihahite contentions and Alma’s responses can be read to tell us not only about Nephite gospel, which is Mormon’s intent, but also about the order of Nehor “gospel.” While this second is certainly not the true gospel, it is nevertheless very significant for our understanding of the dynamics of Nephite historical development. These are the arguments, in one flavor or another, that have and will plague the true believers throughout the Book of Mormon. We first began to see the outlines of this competing religion in the confrontation between Abinadi and the priests of Noah (significantly including Alma the Elder). This contention between the Ammonihahites and Alma the Younger can continue to increase our understanding of this competing religion that was so significant it was considered a threat to the peace of the Nephites.
To this point there is little that we can glean, depending upon how we understand Alma’s comments about the end of the world. It is possible that he is noting that they do not believe in the apocalyptic destruction of the earth at the end of time. This might be a logical result of their denial of the Messiah, though we most frequently see the denial of the Atoning Messiah, not necessarily the Triumphant Messiah.
Rhetorical: The first argument presented by the Ammonihahites is one of authority. While modern LDS readers assume the authority of Alma, the Ammonihahites did not. Their first question to him is “who are thou?” This was not a question of “what is your name and your position,” but one that questioned the essential right of Alma to predict. The note that they would not believe just one man if he were to come and tell them that the world were ending. It is clear from Alma’s inserted comment that they intended this comment sarcastically, because he notes that they did not understand that this truly would happen.
We do not have the context that lets us know why we have these two particular pieces of the exchange, but we may speculate somewhat. First, it is reasonable that Alma had already been doing his job, that is, declaring the destruction of Ammonihah if they did not repent. Certainly they would not believe Alma’s message, since they had no faith in the messenger.