Duane S. Crowther discusses the "White Horse Prophecy," cautiously accepts its authenticity.
Duane S. Crowther, Prophecy: Key to the Future (Salt Lake City: Bookcraft Inc., 1962), 301-22
For many years there has been circulated among the membership of the Church copies of a prophecy attributed to Joseph Smith called the “White Horse Prophecy.” Various general authorities, on several occasions, have held that there is no foundation to the claim that the Prophet made the prophecy and have stated that it is spurious. In spite of this, many have continued to circulate the prophecy and maintain its validity. This appendix article is written to present the facts in order that the reader may make his own decision on the matter.
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Observations Concerning the Prophecy
The reader will note, after examining the prophecy and the evidence given to substantiate it that:
1. The historical events the prophecy records pertaining to the manner it was given are generally in harmony with the history record by the Prophet.
2. Every portion of the prophecy pertaining to the past era of the Saints’ exodus to the West, territorial problems, the fall of the Turkish Empire, etc., has been literally fulfilled.
3. In general, the prophecy conforms to the pattern for the future which is established by the entire series of prophecies quoted in this work.
4. Almost all of the prophecy which is pertaining to the future has been substantiated by similar prophecies or teachings by other General Authorities.
5. There are, however, several areas of conflict. The most serious of these is Rushton’s report on the weather conditions for May 6, 1843. This conflict would seem to indicate that he had waited a considerable time before recording the prophecy, which would raise the question as to the overall accuracy of his recording.
6. The portions of the prophecy pertaining to foreign nations and their relationship to the Church during the period of internal conflict in the United States are generally unsubstantiated. This is the area which refers to the “Horses.” If there was error in recording the prophecy this would most likely be the area in which the errors occurred. This is the portion which has occasioned criticism of this prophecy.
7. If the prophecy is fictitious and is not inspired, then it is extremely remarkable in its conformity to the pattern of prophecy found in the scriptures and statements by General Authorities. Whoever wrote it (and it would apparently be Edwin Rushton) would have to had a familiarity with the prophecies far superior to that of the average Latter-day Saint.
8. While it is impossible to say with certainty that the prophecy is valid and that it was made by Joseph Smith, the overwhelming weight of the evidence at hand causes the author to be of that opinion. Consequently portions of the prophecy have been used in this work in areas where they form part of an established pattern. Until positive proof can be obtained, however, the author feels that the “White Horse Prophecy” should be used with care and discretion.