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Pergunta: Os Mórmons consideram seus profetas para ser infalível?
Question: Do Mormons consider their prophets to be infallible?
Latter-day Saints do not believe that prophets and apostles are incapable of error, despite being called of God and receiving revelation
Some people hold inerrantist beliefs about scriptures or prophets, and assume that the LDS have similar views. This leads some to assume that prophets are infallible. 
Joseph Smith himself taught that ‘a prophet was a prophet only when he was acting as such’. The Church has always taught that its leaders are human and subject to failings as are all mortals. Only Jesus was perfect, as explained in this statement from the First Presidency:
The position is not assumed that the men of the New Dispensation —its prophets, apostles, presidencies, and other leaders—are without faults or infallible, rather they are treated as men of like passions with their fellow men."
Lu Dalton, writing in the Church's periodical for women, explained:
We consider God, and him alone, infallible; therefore his revealed word to us cannot be doubted, though we may be in doubt some times about the knowledge which we obtain from human sources, and occasionally be obliged to admit that something which we had considered to be a fact, was really only a theory.
Other authors have long taught the same thing:
1887 B. H. Roberts, Letter written November 4, 1887, London, Millennial Star 49. 48 (November 28, 1887): 760-763; a portion of which reads: “Relative to these sermons [Journal of Discourses] I must tell you they represent the individual views of the speakers, and the Church is not responsible for their teachings. Our authorized Church works are the Bible, Book of Mormon, Doctrine and Covenants, and the Pearl of Great Price. In the Church very wide latitude is given to individual belief and opinion, each man being responsible for his views and not the Church; the Church is only responsible for that which she sanctions and approves through the formal actions of her councils. So it may be that errors will be found in the sermons of men, and that in their over zeal unwise expressions will escape them, for all of which the Church is not responsible” (762)
1889 Charles W. Penrose, Editorial: Judge Anderson and ‘Blood Atonement,’ Deseret Weekly 39. 25 (December 14, 1889): 772a-773c. [Editor is Charles W. Penrose; in his response to the lengthy statement by Judge Anderson, he quotes from the same pamphlet which the Judge had quoted from: Blood Atonement, by Elder Charles W. Penrose, published in 1884; Penrose quotes a statement which the Judge had not] “’The law of God is paramount. When men give their views upon any doctrine, the value of those views is as the value of the man. If he is a wise man, a man of understanding, of experience and authority, such views are of great weight with the community; but they are not paramount, nor equal to the revealed law of God’” (773ab)
1892 21 March 1892: Elder Charles W. Penrose, at the time a counselor in the Salt Lake Stake Presidency: "At the head of this Church stands a man who is a Prophet . . . we respect and venerate him; but we do not believe that his personal views or utterances are revelations from God." Millennial Star 54 (21 March 1892): 191
1902 Joseph F. Smith to Lillian Golsan, July 16, 1902. "[T]he theories, speculations, and opinions of men, however intelligent, ingenious, and plausible, are not necessarily doctrines of the Church or principles that God has commanded His servants to preach. No doctrine is a doctrine of this Church until it has been accepted as such by the Church, and not even a revelation from God should be taught to his people until it has first been approved by the presiding authority–the one through whom the Lord makes known His will for the guidance of the saints as a religious body. The spirit of revelation may rest upon any one, and teach him or her many things for personal comfort and instruction. But these are not doctrines of the Church, and, however true, they must not be inculcated until proper permission is given.” - Joseph F. Smith Correspondence, Personal Letterbooks, 93–94, Film Reel 9, Ms. F271; cited in Dennis B. Horne (ed.), Determining Doctrine: A Reference Guide for Evaluation Doctrinal Truth (Roy, Utah: Eborn Books, 2005), 221–222. Also in Statements of the LDS First Presidency, compiled by Gary James Bergera (Signature, 2007), page 121. Bergera indicates it is a letter from JFS to Lillian Golsan, July 16, 1902.
1907 March 26, 1907. [The following was first published in “An Address. The Church of Jesus Christ of Latter-day Saints to the World”, in Millennial Star 69. 16 (April 18, 1907): 241-247; 249-254; also in Improvement Era 10 (May 1907): 481-495; reprinted also in Messages of the First Presidency, Volume IV, compiled by James R. Clark (Bookcraft, SLC 1970): 142-157; “We refuse to be bound by the interpretations which others place upon our beliefs, or by what they allege must be the practical consequences of our doctrines. Men have no right to impute to us what they think may be the logical deduction from our beliefs, but which we ourselves do not accept. We are to be judged by our own interpretations and by our own actions, not by the logic of others, as to what is, or may be, the result of our faith”, page 154.
1921 B.H. Roberts: As to the printed discourses of even leading brethren…they do not constitute the court of ultimate appeal on doctrine. They may be very useful in the way of elucidation and are very generally good and sound in doctrine, but they are not the ultimate sources of the doctrines of the Church, and are not binding upon the Church. The rule in that respect is—What God has spoken, and what has been accepted by the Church as the word of God, by that, and that only, are we bound in doctrine. When in the revelations it is said concerning the Prophet, Seer, and Revelator that the Church shall “give heed unto all his words and commandments which he shall give unto you as he receiveth them—for his word ye shall receive as if from mine own mouth, in all patience and faith”—(Doc & Cov., Sec. 21)—it is understood, of course, that his has reference to the word of God received through revelation, and officially announced to the Church, and not to every chance word spoken.
The prophets are not perfect, but they are called of God. They may speak as men, but may speak scripture as well. Every person may know for themselves whether they speak the truth through the same power that their revelation is given: the power of the Holy Ghost.
- Criticisms regarding assumptions of prophetic infallibility are raised in the following publications: Predefinição:CriticalWork:Dehlin:Why People Leave the LDS Church:2008; Bill McKeever and Eric Johnson, Mormonism 101. Examining the Religion of the Latter-day Saints (Grand Rapids, Michigan: Baker Books, 2000), Chapter 18. ( Index of claims ); Jerald and Sandra Tanner, The Changing World of Mormonism (Moody Press, 1979), 437. ( Index of claims ); Tower to Truth Ministries, "50 Questions to Ask Mormons," towertotruth.net (accessed 15 November 2007). 50 Answers; Watchman Fellowship, The Watchman Expositor (Page 1)
- Joseph Smith, History of The Church of Jesus Christ of Latter-day Saints, 7 volumes, edited by Brigham H. Roberts, (Salt Lake City: Deseret Book, 1957), 5:265. BYU Studies link; See also Joseph Smith, Jr., Teachings of the Prophet Joseph Smith, selected by Joseph Fielding Smith, (Salt Lake City: Deseret Book Company, 1976), 278. ISBN 087579243X. off-site
- James R. Clark, quoting B. H. Roberts, Messages of the First Presidency, edited by James R. Clark, Vol. 4, (Salt Lake City: Bookcraft, 1970), p. xiv–xv.
- Lu Dalton, Woman's Exponent (Salt Lake City: 15 July 1882), p. 31.
- Brigham H. Roberts, “Answer Given to ‘Ten Reasons Why “Christians” Can Not Fellowship with Latter-Day Saints,’” discourse delivered in the Salt Lake Tabernacle, 10 July 1921. Deseret News, 23 July 1921, 4:7. Roberts' previous reply to the same pamphlet also appeared in His earlier response can be found in Brian H. Stuy (editor), Collected Discourses: Delivered by Wilford Woodruff, his two counselors, the twelve apostles, and others, 1868–1898, 5 vols., (Woodland Hills, Utah: B.H.S. Publishing, 1987–1989), 5:134-141. ; it was first published in Millennial Star 58 (July 22, 1896): 417-20; 433-9.