It is not at all surprising that the people of Ammonihah did not like Alma’s depiction of them. It was not at all flattering, and they were probably a people more used to public flattery than public calls to repentance. As a result, they were angry, and attempted to take Alma to prison. Alma does not tell us precisely how they were prevented from doing so, only that it was the Lord who prevented that occurrence. The Lord certainly prevented it because he wanted Amulek to speak.