"The Testimony of Jesus Is the Spirit of Prophecy"
Revelation 19:9; 9b. He saith unto me] Who is speaking to John? It is none other than the angel sent of God to stand in the place and stead of the Lord Jesus Christ in giving the Beloved Revelator all those things recorded in the Book of Revelation. See Revelation 1:1-6, 12-20; 22:6-16.
Revelation 19:9; In their epistle of June 30, 1916, setting forth the relationship of the Father and the Son to each other and man's relationship to each of them, the First Presidency and the Council of the Twelve, having first quoted various scriptures bearing upon the point, say this: "Thus the Father placed his name upon the Son; and Jesus Christ spoke and ministered in and through the Father's name; and so far as power, authority and Godship are concerned his words and acts were and are those of the Father.
Revelation 19:9; "We read, by way of analogy, that God placed his name upon or in the Angel who was assigned to special ministry unto the people of Israel during the exodus. Of that Angel the Lord said: 'Beware of him, and obey his voice, provoke him not; for he will not pardon your transgressions: for my name is in him.' (Exodus 23:21.)
Revelation 19:9; "The ancient apostle, John, was visited by an angel who ministered and spoke in the name of Jesus Christ." Here they quote Revelation 1:1, and then say: "John was about to worship the angelic being who spoke in the name of the Lord Jesus Christ, but was forbidden." Revelation 22:8-9 is then quoted, in which the angel says he is John's fellow servant and one of his brethren among the prophets. "And then the angel continued to speak as though he were the Lord himself: 'And, behold, I come quickly; and my reward is with me, to give every man according as his work shall be. I am Alpha and Omega, the beginning and the end, the first and the last.' (Revelation 22:12-13.) The resurrected Lord, Jesus Christ, who had been exalted to the right hand of God his Father, had placed his name upon the angel sent to John, and the angel spoke in the first person, saying, 'I come quickly,' 'I am Alpha and Omega,' though he meant that Jesus Christ would come, and that Jesus Christ was Alpha and Omega." (Cited, Joseph Fielding Smith, Man: His Origin and Destiny, pp. 117-129; James E. Talmage, Articles of Faith, pp. 465-473.)
Revelation 19:9; These are the true sayings of God] The angel, in the Lord's name, bears testimony of the truth and divinity of his teachings and ministerial acts—setting a perfect example of testimony bearing for all the Lord's agents in all ages.
Revelation 19:10; 10. Thy fellowservant... thy brethren] The Lord's servants in every state and stage of eternal progression—those yet in pre-existence; those dwelling as mortals on earth; those in the paradise of God; those who have been translated; and those who have come forth in the resurrection—all the Lord's servants in all spheres of existence are brethren, fellow laborers, fellow servants.
Revelation 19:10; The testimony of Jesus] The revealed knowledge of the divinity of the Lord and his work. See 2 Timothy 1:1-12.
Revelation 19:10; The spirit of prophecy] Since the greatest and most important revealed truth in all eternity is that Jesus Christ is the Son of the living God and that he was crucified for the sins of the world; since this truth is and can be known only by revelation from the Holy Ghost; since prophecy consists of what holy men speak when they are moved upon by the Holy Ghost (2 Peter 1:20-21); it follows that any person who has a testimony is a prophet, as Joseph Smith, citing this very passage declared. See Commentary I, pp. 251-253; Commentary II, pp. 381-388.