Ammon asks the queen if she believes, and she does—but adds that it is on the basis of testimony from Ammon and the servants. In other words, no logical argument and no manifestation of the Spirit have confirmed her faith.
In this simple ability to believe based upon another’s testimony, the queen is laying claim to one of the most powerful of the gifts of the Spirit: “To some it is given by the Holy Ghost to know that Jesus Christ is the Son of God, and that he was crucified for the sins of the world. To others it is given to believe on their words, that they also might have eternal life if they continue faithful” (D&C 46:13–14). Some are blessed by a direct witness of the Spirit. Certainly Ammon’s experience with Alma either qualifies or comes close. Lamoni was also experiencing this direct, personal witness of the Spirit. While the Doctrine and Covenants focuses on obtaining a testimony that Jesus is the Son of God, the principle clearly applies to any gospel principle about which the Spirit bears direct witness.
Those who know certainly have a gift, but others have the gift of the ability to believe. They apparently do not need the Spirit’s personal confirmation but, like this Lamanite queen, may sincerely believe because of faith in other’s words.