Mormon’s editorial process necessarily leaves out certain pieces of information. The father of Lamoni is interested in what Aaron has to say because of his experience with Ammon. This verse makes it appear that one of the points on which the over-king has questions is about the Spirit of the Lord. This would appear to be a phrase that he had learned in connection with Ammon. Our record, however, never tells of any conversation including the phrase “Spirit of the Lord” between Ammon and the over-king.
Nevertheless, we may assume that it was contained in the explanations among Ammon, Lamoni and his father. This Spirit of the Lord was instrumental in moving Lamoni from unbeliever to believer, and it is most likely this context that has the over-king most curious as to what happened to his son. Therefore Aaron begins with a simple statement addressing Ammon’s current location, and the king focuses on the phrase that is important to him, and likely the reason that he has allowed the Nephites into his court and still refused them as servants.