Alma provides a promise to the people of Gideon. Those who are baptized (“whosoever doeth this”) and keep the commandments, will have eternal life.
Textual: This verse has an interesting “correction.” Alma begins in the present tense, and then shifts to the past tense: “will remember that I say unto him, yea, he will remember that I have said unto him…” There are two possibilities for this shift. The first is that it is an accurate transcription of Alma’s discourse. In a live discourse, it would not be surprising that Alma might use the present tense, and then realize that he was speaking of a future state of his audience, when his current words would necessarily be past.
The second possibility is that this is part of a dictation sequence by Joseph. Since there is a logical explanation for the original, the first possibility is the most likely. However, there are several such shifts, and the possibility that they represent an artifact of the dictation sequence should not be dismissed to quickly.