There are two important aspects of Korihor’s confession. The first is that Korihor admits the deception that Alma had already perceived. Korihor had known that there was a God, and he was deceiving when he denied God, just as Alma had said. The more interesting information is how Korihor came to this conclusion. The devil appeared to him as an angel, and mislead him. This piece of information has both a social and a literary significance.
Literary: Korihor is not only Anti-Christ, but he is here Anti-Alma. We have noted that it is no coincidence that Korihor is presented right after the successful mission of the sons of Mosiah. At this point the literary parallelism shifts away from the sons of Mosiah and directly to Alma. The confrontation between Alma and Korihor is here presented as a linked opposition. Both Alma and Korihor were believers in something, both had a visitation by an angel, both were converted by that experience, and both preached to the people the gospel learned in that experience. Korihor and Alma are too similar to be accidental. They have only one fundamental difference, and that is that Alma is converted to true, and Korihor to error. That conclusion is powerfully underlined in the curse Korihor receives because of his continued demand for a sign.
Social: How could Korihor have seen a devil as an angel? This is not really a theological question, but a very important one in the Mesoamerican context in which we are placing the events of the Book of Mormon. We have the terms devil and angel as loaded religious terms, and we assume that “devil” is “The Devil;” and that “angel” is “messenger from God.” These may not have been the original terms nor the original meanings. When the Spaniards discussed native gods, they always referred to them as devils. In their Western Christian experience there was one True God, and anything else was not only false, but a devil. In the Mesoamerican experience there were many other gods of the Lamanites, and the dichotomous Christian language Joseph used to translation the plates could easily replicate the Spanish appellation of the native gods as devils.
In the Mesoamerican religious system, the gods were frequently present in the world. The function of the Maya bloodletting rites was to communicate with the gods, and to materialize them into this world (Schele and Freidel. A Forest of Kings. William Morrow and Company, 1990, p. 426-7). In the context of a world view that materialized the gods in vision, it is quite possible that Korihor had undergone such a rite, with the attendant hallucinogenic effect of materializing a god – or in Korihor’s case, an angel. There is no indication that Korihor was a king, and the materialization of the gods would be reserved for the kings, but certainly the principle would have been known, and the practice of bloodletting extended beyond the kings.