Rhetoric: Alma formally calls for repentance. Repentance is the process by which ungodly characteristics are stripped away and God’s healing hand may touch us. This is a greater call than to simply cease an undesirable act. Alma is not simply saying that they should stop being prideful but that they should repent of being prideful. He is not only saying to stop persecuting, but to repent of persecuting. Where stopping is a physical action, repenting is a spiritual one. There are tremendous differences to the soul between ceasing an untoward act and repenting from it. (See “Excursus: The Principle of Repentance,” following 3 Nephi 18.)
And while Alma has made it abundantly clear that there is no acceptance for those who have committed the particular sins he has mentioned (and not repented), he promises Yahweh’s acceptance and welcome, even embrace, for those who do repent.