Alma begins his discourse by asking if they remember the times their fathers have been delivered by the hand of God. Of course this flows from his appeal to the fathers, but the theme is more important to Alma than that. This is precisely the way he began his discourse to the congregation in Zarahemla as he began this “revival tour” (see Alma 5:3-6). He will repeat this same theme in Alma 29:12, Alma 36:28-29, and Alma 60:20. Why is this theme so important to Alma’s attempts at creating a communal repentance?
The answer probably lies in the most dramatic personal experience of Alma’s life, his experience with the angel that turned his own life around. Notice the language of the angel on that occasion:
Mosiah 27:16-17
16 Now I say unto thee: Go, and remember the captivity of thy fathers in the land of Helam, and in the land of Nephi; and remember how great things he has done for them; for they were in bondage, and he has delivered them. And now I say unto thee, Alma, go thy way, and seek to destroy the church no more, that their prayers may be answered, and this even if thou wilt of thyself be cast off.
17 And now it came to pass that these were the last words which the angel spake unto Alma, and he departed.
One of the ways that the angel impressed upon Alma the need for his repentance and return to full commitment to the Nephite religion was to remind him of the captivity and divine salvation of his fathers by the hand of God. In the context of the rest of that angelic visitation, this must have seemed like a capstone argument, surely it convinced Alma (along with the rest of the experience). For Alma, it would appear that his own conversion was so intimately linked with his understanding of the hand of God in the history of his fathers, that he assumed that the logic of that argument would have a similar conversion power among other peoples to whom he preached. Alma is not using an idle example here, but one that was of tremendous personal importance to him. Alma is using his best efforts to cause the repentance of these people.