Mormon describes the setting for Alma’s address as probably outside the city, since they were assembled on a hill. He addresses one group, but interrupts himself when a new group arrives. This second group is described as poor “as to the things of the world,” suggesting that they were in worse economic circumstances than the first group. Since Antionum had only two social classes, Alma (or Mormon) apparently used “poor” as a synonym for “humble.” Both groups are humbler than the elite, but the second group is sufficiently humble (“poorer”) that they are more teachable.
Culture: Alma speaks to people on a hill because he can be seen and heard more readily by a larger congregation. Presumably he was closer to the hilltop than his listeners. Pragmatically, the advantages to the speaker are that it is easier for one person to climb a hill than for the entire congregation to do so.
However, I also suggest some cultural advantages. First, it would recall to the listener the setting of temple pyramids. From the platform at the top, the speaker would address the congregation gathered in the courtyard. Second, mountains in Mesoamerica had connotations of sanctity. On such mountains, communication could occur between the heavens, the earth’s surface, and the underworld. Such connotations were the very reason for building pyramids; they were artificial mountains. For Alma, using a hill from which to preach the gospel would employ these connotations of preaching about sacred things in a naturally sacred location.
Third, by using the hill—a natural feature—Alma was unconsciously underscoring the difference between the city’s artificiality (including its artificial elite) and the natural world of the country, where the farmer-poor were in their element, no longer subservient.
Geography: The hill is named Onidah, a place identified in Alma 47:5 as “the place of arms.” Reynolds and Sjodahl note the repeated name but suggest that the same name has been given to two different locations. Since the Lamanites flee to Onidah after the threat of a military attack, it may be an armory. Clearly, Alma is preaching from a literal hill, not a building; its only connection to “a place of arms” is the name itself.
The settings of the two mentions of a hill Onidah also suggest separate locations. The Onidah of Alma 47 is near Lehi-Nephi in the heart of Lamanite country, while Alma’s hill is in Nephite territory, even though it is near a wilderness where there are Lamanites. Sorenson suggests that the hill Onidah might contain an outcropping of obsidian, a material much used in Mesoamerican cutting instruments, including weapons. If the name derives from the presence of obsidian, there would be a logical reason to have more than one location with that name.