O that I were an angel, and could have the wish of mine heart, that I might go forth and speak with the trump of God, with a voice to shake the earth, and cry repentance unto every people!
Yea, I would declare unto every soul, as with the voice of thunder, repentance and the plan of redemption, that they should repent and come unto our God, that there might not be more sorrow upon all the face of the earth.
This became the wish of Alma (the younger), who, from personal experience knew all about the impact of angelic ministry (Mosiah 27:11-23). Little did he know that just one chapter later his wish would, in many ways, be granted.
Alma was once known as "a man of many words" which he used to "speak much flattery" and lead "many of the people to do after the manner of his iniquities" (Mosiah 27:8). It's quite possible that he saw much of his former self in Korihor, who "rose up in great, swelling words" before him.
Recall, for a moment, the final words spoken by the angel to Alma at his first appearance (yes, there was another appearance of the same angel to Alma later in his life):
...And now I say unto thee, Alma, go thy way, and seek to destroy the church no more, that their prayers may be answered, and this even if thou wilt of thyself be cast off.
If was then that Alma lost the ability to speak or even move for two days. Footnote 'd' in Mosiah 27:16 (quoted above) points to Alma 30:47, which contains the final words of Alma to Korihor:
But behold, it is better that thy soul should be lost than that thou shouldst be the means of bringing many souls down to destruction, by thy lying and by thy flattering words; therefore if thou shalt deny again, behold God shall smite thee, that thou shalt become dumb, that thou shalt never open thy mouth any more, that thou shalt not deceive this people any more.
Both the angel's words to young Alma and older Alma's words to Korihor bear a similar message, and had similar effects on the listener:
I assume that Alma and Korihor experienced different outcomes because of the level and extent of their rebellion in relation to the knowledge they had at the time. Whereas Alma received the Angel's visit in order to be convinced of the power and existence of God (Mosiah 27:14), Korihor "always knew that there was a God" (Alma 30:52).
Even though Alma admitted that his desire for angelic authority was born of personal discontent and was somewhat sinful, it illustrates several points: