Mormon sets up the conflict that will play out in the next several chapters. Alma came to preach the word of God, but “Satan had gotten great hold upon the hearts of the people of the city of Ammonihah.” Thus, the essential dichotomy is established. This is a story of the conflict between Good and Evil, but demonstrated on a very human scale in a very human and understandable context.
We see that Alma “labored much in the spirit, wrestling with God in mighty prayer.” Reading that, a reader might understandably expect that a clearly righteous leader, one who had been dramatically saved through God’s direct intervention, might prevail through mighty prayer and succeed.
That will not be the case.