Rhetorical: Alma is bearing testimony, and is certainly invoking his own conversion experience, which is equally certain to have been know to his congregation. However, it is also possible that Alma intends his question "do ye not suppose that I know these things of myself?" to have a dual meaning. For the purposes of his testimony, he surely knows of the "things which are to come" (verse 44) because of his own experience. However, the nature of his conversion was from evil to good. Alma may be very directly discussing not only the positive aspects of repentance, but very specifically the road of those who have chosen to follow Satan. Alma knew that road intimately prior to his conversion. When Alma is preaching to his congregation of the fate of those who chose to follow Satan, he is also preaching from personal experience. Fortunately for all of us, he also preaches from the knowledge of the power of repentance, a course that he is actively recommending to his congregation.