In verses 10 to 11, Alma asked seven more questions. He took his audience through them—again, in kind of a lawyerly way—in an ordered step by step process of understanding some of the most basic principles of the gospel.
"What was the cause of your fathers being loosed?" (5:10). He was asking about the conditions, about the cause and effect of spiritual blessings. We need to think about that too. Part of the essential logic of the gospel is that there are consequences. Because of that, we can rely on certain outcomes, and we can therefore have hope. Alma did not stop and explain here, but he was not just asking his people to think on what conditions those others were saved. Of course, he wants us to be thinking and asking ourselves, on what conditions will I be saved?
Does God require us to hope for things that are without foundation? No. True faith is believing in things that are true, and we have a reason for the hope that is in us (1 Peter 3:15). And that understanding is the next thing that we learn from thinking about these conditions. On what grounds did they have hope for salvation? That God will come into their lives, and will cause them to be loosed from the bands of death and of hell. That happens when Satan is driven out of our lives. That is the next step in Alma’s instructions.
In question nine, Alma asked, "Did not my father Alma believe in the words which were delivered from the mouth of Abinadi?" (5:11). They were expected to believe the words of the prophet. Not only to believe the words—the next question was, "Was Abinadi not a holy prophet?" We also must not only believe that he was a prophet and believe in his words, but we also must believe in his holy calling as an authorized messenger and agent of God who would deliver those blessings.
Question number eleven, the sixth question in this set, is, "Did Abinadi not speak the words of God?" (5:11). No one in that audience was going to doubt that Abinadi spoke the words of God; they saw his prophecies fulfilled, thus defining him as a true prophet. They would have known the law about prophets in Deuteronomy 18:21 asks how one may know a true prophet from a false one, "And if thou say in thine heart, How shall we know the word which the Lord hath not spoken?" The key for knowing is then provided, "When a prophet speaketh in the name of the Lord, if the thing follow not, nor come to pass, that is the thing which the Lord hath not spoken, but the prophet hath spoken it presumptuously: thou shalt not be afraid of him" (Deut. 18:22).
In Alma’s audience on this solemn occasion were still some of the people who followed Alma’s father as they fled from King Noah. In this audience also were people who had come from the city of Nephi with Limhi. They and everyone there knew these stories, and all of them would have to agree that Abinadi was a true prophet.
Book of Mormon Central, "How Does Prophecy Shape the Book of Mormon’s Content and Structure? (Words of Mormon 1:4)," KnoWhy 498 (January 15, 2019).