Alma had seen an angel, but he testified in Alma 5:46–47 that it was fasting and prayer that had allowed him to come to know, not seeing an angel. President Heber J. Grant (1856–1945) explained: “Many men say: ‘If I could only see an angel, if I could only hear an angel proclaim something, that would cause me to be faithful all the days of my life!’ It had no effect upon these men [Laman and Lemuel] that were not serving the Lord, and it would have no effect today” (in Conference Report, Apr. 1924, 159).
President Joseph Fielding Smith (1876–1972) explained why the Holy Ghost can be more powerful than a visitation of an angel: “Christ … declared that the manifestations we might have … from a visitation of an angel, a tangible resurrected being, would not leave the impression … which we receive through a manifestation of the Holy Ghost. Personal visitations might become dim as time goes on, but this guidance of the Holy Ghost is renewed and continued, day after day, year after year, if we live to be worthy of it” (Doctrines of Salvation, comp. Bruce R. McConkie, 3 vols. [1954–56], 1:44).
The spirit of revelation is communication from God to man by the power of the Holy Ghost to the mind and heart (see D&C 8:2). Elder Richard G. Scott of the Quorum of the Twelve Apostles described how to recognize communication from the Holy Ghost:
“An impression to the mind is very specific.
“Detailed words can be heard or felt and written as though the instruction were being dictated.
“A communication to the heart is a more general impression. The Lord often begins by giving impressions. Where there is a recognition of their importance and they are obeyed, one gains more capacity to receive more detailed instruction to the mind. An impression to the heart, if followed, is fortified by a more specific instruction to the mind” (“Helping Others to Be Spiritually Led” [Church Educational System symposium on the Doctrine and Covenants, Aug. 11, 1998], 3–4; see LDS.org under gospel library/additional addresses/CES addresses).