Here is the second point of contention with Alma. The first is that Corianton boasted of his own strength. The second is the result of that boasting. By filling in the blanks of what Alma does not tell us, the evidence of which will continue to mount as we examine Alma’s discourse to his son, we may understand the nature of what Corianton did.
In this case we have some obvious information, and some not-so-obvious information. First, it is obvious that Corianton both abandoned his mission, and that he took up with a harlot. We in the modern world understand that both of these events would be cause for great sorrow should they occur to a missionary. What we do not as easily understand is the rest of the story that is told to us in these brief statements.
First, we have the fact that Corianton abandoned his mission. While this is important information, we need to understand why. We must understand that when the mission to the Zoramites began, Shiblon and Corianton were likely both considered righteous. There is no indication from Alma that Corianton was lukewarm in his approach to the gospel prior to the mission to the Zoramites. What we are told is that he boasted in his own strength. While that is a foreshadowing of a fall, it is nevertheless an indication of some beginning position of strength.
Thus what we see in the departure is a personal apostasy from the gospel, something that must have been very personally painful to his father, since Alma the Younger would have well understood the temptations of that non-gospel centered life. Alma would be watching a son take the opposite life-path from the one that Alma described to both Helaman and Shiblon, where Alma turned away from apostasy and toward Christ. Corianton and gone through an event (the mission to the Zoramites) that has made a parallel turn in his life, but in an entirely different direction.
The second event is that Corianton did “go after” the harlot Isabel. What we might miss is that this “harlot” is “among the borders of the Lamanites.” This direction is probably as significant as the time spent with Isabel. Isabel is apparently not necessarily Zoramite, but Lamanite. At the very least, there is the implication of direction here that is more than physical. Corianton did not simply physically move towards the Lamanites, he is culturally and spiritually moving towards the Lamanites. When he leaves his mission, he does not go home, he goes in the opposite direction both physically and spiritually.
We do not know much about the harlot Isabel, though it is fascinating that she is named. She is one of the few named females in the Book of Mormon, and the fact of her naming suggests that she has some importance. Indeed, we will learn in the next verse that Corianton is not the only one whose heart was stolen away. While the sexual connotations are explicit and should not be underplayed, it is quite possible that there is more than simple sexual union going on here. In many pagan religions it is not uncommon for priestesses to engage in sexual unions that are considered sacred because of person or place in that religion.
The naming of this woman may suggest that above the sexual connotation we should see the spiritual turning as well. Corianton’s adoption of a new worldview, a new concept of religion, would place in him in a position where his opinions of sexual congress would also have changed. While the clearly unmarried act of sexual union would be sufficient, it is not certain that this is all we are to understand here. It is quite probable that there is a cultural context that Alma does not need to explain, but which would have been very helpful to modern readers.