Limhi sees Ammon as a means of entering into the same covenant that Alma had made with Yahweh and into which he had introduced his people. Indeed, the Limhites had already made the covenant in their hearts (v. 32) but were awaiting the ordinance of baptism which would seal the covenant. Having seen (or at least heard reports of) Alma and his church, they wanted that same benefit for themselves and hoped that Ammon could give them the benefits of Alma’s baptism. Ammon declines, not because he lacks authority, but because he sees himself as “an unworthy servant.” Daniel C. Peterson suggests that Ammon felt “unworthy” because he was a warrior. I believe that there were even more forces at play.
The Limhites have already delayed baptism because “there was none in the land that had authority from God.” They assumed that Ammon, coming from Zarahemla, would possess such authority. Ammon neither confirms nor denies that point. Ammon appears to hesitate for reasons more complex than just the worthiness to perform a baptism. (See commentary following vv. 34–35.)