Rhetorical: Alma is giving a historical recitation. This is not a specific history of Ammonihah, but of the “fathers” to whom they look as a spiritual foundation. Alma has attempted to connect Ammonihah to these fathers, and now uses the faith of the fathers to contrast with the lack of faith of these particular sons.
Alma returns to the fathers and lists blessings that Ammonihahites should accept without question as part of the myth of the founders (using the anthropological sense of the word myth). This catalog of the blessings now stands as a condemnation of Ammonihah where the Ammonihahites would most likely have looked to those legends as part of their own personal justification. Alma is continuing to turn their own traditions upon them, to create unexpected contrasts that will jog them out of their current state of apostasy.