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Question: Are Latter-day Saints taught to look down upon or reject those who are not of their faith?
Question: Are Latter-day Saints taught to look down upon or reject those who are not of their faith?
Mormons have always been taught that a dismissive attitude toward the beliefs or faith of others is sinful
The attitude that one ought to look down upon or reject those who are not of their faith is an abhorrent one. Members of the Church, of course, do not always live up to these high standards. But, there can be no doubt as to what the standards are:
What does the Lord expect of us as Latter-day Saints? What does He expect of me as a member of this Church...There is no room in the heart of a Latter-day Saint for bitterness, for unkindness, for animosity to any other of the sons and daughters of God. They may not be of our faith, but we owe them an obligation to treat them as sons and daughters of our Father in Heaven. 
Mormons have always been taught that a dismissive attitude toward the beliefs or faith of others is sinful. (Indeed, the Book of Mormon condemns in the strongest terms those who adopt such an attitude: Alma 31:16-19, Alma 31:27-35).
Joseph Smith: "We should gather all the good and true principles in the world and treasure them up, or we shall not come out true 'Mormons'"
Said Joseph Smith:
Have the Presbyterians any truth? Yes. Have the Baptists, Methodists, etc., any truth? Yes. They all have a little truth mixed with error. We should gather all the good and true principles in the world and treasure them up, or we shall not come out true "Mormons." 
Gordon B. Hinckley: "There is no room for arrogance in our lives. There is no room for conceit in our lives. There is no room for egotism in our lives"
Warned President Gordon B. Hinckley:
There is no room for arrogance in our lives. There is no room for conceit in our lives. There is no room for egotism in our lives. We must be humble before the Lord. He has so declared, and if we will do it, He will hear our prayers and answer them with a blessing upon our heads. 
Of the specific conceit which some claim they are taught, President Hinckley said:
Be respectful of the opinions and feelings of other people. Recognize their virtues; don't look for their faults. Look for their strengths and their virtues, and you will find strength and virtues that will be helpful in your own life. 
It's hard to see how looking for "strengths and...virtues" in non-members to help an LDS member's own life constitutes ignoring or deprecating all non-believers.
President Hinckley further said:
There is no need in any land for conflict between diverse groups of any kind. Let there be taught in the homes of people that we are all children of God, our Eternal Father, and that as surely as there is fatherhood, there can and must be brotherhood. 
He denounced bad feelings and behavior toward non-Mormons:
Why do any of us have to be so mean and unkind to others? Why can't all of us reach out in friendship to everyone about us? Why is there so much bitterness and animosity? It is not a part of the gospel of Jesus Christ. We all stumble occasionally. We all make mistakes. I paraphrase the words of Jesus in the Lord's Prayer: "And forgive us our trespasses, as we forgive those who trespass against us."
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There is no end to the good we can do, to the influence we can have with others. Let us not dwell on the critical or the negative. Let us pray for strength; let us pray for capacity and desire to assist others. Let us radiate the light of the gospel at all times and all places, that the Spirit of the Redeemer may radiate from us. 
Members and non-members have the same status before God. This does not support the idea that members are to "hold themselves aloof."
Ezra Taft Benson: "God, the Father of us all uses the men of the earth, especially good men, to accomplish his purposes"
God, the Father of us all uses the men of the earth, especially good men, to accomplish his purposes. It has been true in the past, it is true today, it will be true in the future. 
President Benson then quoted Elder Orson F. Whitney from 1928:
Perhaps the Lord needs such men on the outside of His Church to help it along. They are among its auxiliaries, and can do more good for the cause where the Lord has placed them, than anywhere else…God is using more than one people for the accomplishment of His great and marvelous work. The Latter-day Saints cannot do it all. It is too vast, too arduous for any one people…They [other churches] are our partners in a certain sense. 
Joseph Fielding Smith: "the Lord would pour out his blessings and his Spirit upon all people and use them to accomplish his purposes"
Joseph Fielding Smith discussed the prophecy in Joel that God would pour out his spirit "upon all flesh":
Now, my brethren and sisters, I am not going to confine this prophecy [Joel 2:28-29] to the members of the Church. The Lord said he would pour out his Spirit upon all flesh. That does not mean that upon all flesh the Holy Ghost should be sent, and that they should be participants in the blessings which those are privileged to receive who have been baptized and endowed and become members of the Church; but the Lord would pour out his blessings and his Spirit upon all people and use them to accomplish his purposes....
There has never been a step taken..., in discovery or invention, where the Spirit of the Lord (that is, the Spirit of which Joel spoke, the Light of Christ, not the Holy Ghost!) was not the prevailing force, resting upon the individual, which caused him to make the discovery or the invention. The world does not understand that, but it is perfectly clear to me; nor did the Lord always use those who have faith, nor does he always do so today. He uses such minds as are pliable and can be turned in certain directions to accomplish his work, whether they believe in him or not. 
M. Russell Ballard: "I encourage you to build personal, meaningful relationships with your nonmember friends and acquaintances"
I encourage you to build personal, meaningful relationships with your nonmember friends and acquaintances...If they are not interested in the gospel, we should show unconditional love through acts of service and kindness, and never imply that we see an acquaintance only as a potential convert...We must not reserve our kindness and affection only for our fellow members. We must be sensitive and not oblivious to the feelings of those whose views may differ from ours. Considering the early history of the Church in these latter days, unkindness or indifference toward others should be abhorrent to members of the Church. I bear my testimony that "God is no respecter of persons"; we should follow his example in all of our associations with our fellowmen. 
David B. Haight: "we are commanded to do what to many is a more difficult commandment—to love all, even enemies, and to go beyond the barriers of race or class or family relationships"
Besides loving God, we are commanded to do what to many is a more difficult commandment—to love all, even enemies, and to go beyond the barriers of race or class or family relationships. It is easier, of course, to be kind to those who are kind to us— the usual standard of friendly reciprocity.
Then are we not commanded to cultivate genuine fellowship and even a kinship with every human being on earth? Whom would you bar from your circle? We might deny ourselves a nearness to our Savior because of our prejudices of neighborhood or possessions or race—attitudes that Christ would surely condemn. Love has no boundary, no limitation of good will. 
Jeffrey R. Holland: "I testify that no one of us is less treasured or cherished of God than another"
Brothers and sisters, I testify that no one of us is less treasured or cherished of God than another. I testify that He loves each of us—insecurities, anxieties, self-image, and all. He doesn't measure our talents or our looks; He doesn't measure our professions or our possessions. He cheers on every runner, calling out that the race is against sin, not against each other. I know that if we will be faithful, there is a perfectly tailored robe of righteousness ready and waiting for everyone... 
Neal A. Maxwell: "Love is the only answer"
Love is the only answer, as Thomas Merton points out, to the searching question asked by Gandhi when he said: "How can he who thinks he possesses absolute truth be fraternal?" 
Russell M. Nelson: "Learn to listen, and listen to learn from neighbors"
Learn to listen, and listen to learn from neighbors. Repeatedly the Lord has said, "Thou shalt love thy neighbour." (Lev. 19:18; Matt. 19:19.) Opportunities to listen to those of diverse religious or political persuasion can promote tolerance and learning. And a good listener will listen to a person's sentiments as well...The wise listen to learn from neighbours. 
Brigham H. Roberts: "God raises up wise men and prophets here and there among all the children of men"
While the Church of Jesus Christ of Latter-day Saints is established for the instruction of men; and it is one of God's instrumentalities for making known the truth yet he is not limited to that institution for such purposes, neither in time nor place. God raises up wise men and prophets here and there among all the children of men, of their own tongue and nationality, speaking to them through means that they can comprehend. ... All the great teachers are servants of God; among all nations and in all ages. They are inspired men, appointed to instruct God's children according to the conditions in the midst of which he finds them. 
- Gordon B. Hinckley, Meeting, Jakarta, Indonesia, 28 January 2000; cited in Liahona (February 2001): 28.
- History of the Church, 5:517. Volume 5 link
- Gordon B. Hinckley, at a meeting in Winnipeg, Manitoba, Canada, 4 August 1998, cited in Liahona (Aug. 1999): 14.
- Gordon B. Hinckley, cited in Sheri L. Dew, Go Forward with Faith: The Biography of Gordon B. Hinckley (Salt Lake City: Deseret Book, 1996), 536, 576.
- Gordon B. Hinckley, "Four Simple Things to Help Our Families and Our Nations," Liahona (June 1996): 3. off-site
- Gordon B. Hinckley, "The Need for Greater Kindness," General Conference address, 1 April 2006. off-site
- Ezra Taft Benson, Conference Report (April 1972), 49.
- Orson F. Whitney, Conference Report (Aprili 1928), 59.
- Joseph Fielding Smith, Doctrines of Salvation, comp. Bruce R. McConkie, 3 vols., (Salt Lake City: Bookcraft, 1954–56), 176–178. (italics in original)
- M. Russell Ballard, "The Hand of Fellowship," Ensign (November 1988), 28. (emphasis added) off-site
- David B. Haight, "Love All," Ensign (November 1982), 10. off-site
- Jeffrey R. Holland, "The Other Prodigal," Ensign (May 2002), 62. off-site
- Neal A Maxwell, A More Excellent Way: Essays on Leadership for Latter-day Saints, (Salt Lake City: Deseret Book Company, 1967), 31.
- Russell M. Nelson, "Listen to Learn," Ensign (May 1991), 22. off-site
- Brigham H. Roberts, Defense of the Faith and the Saints, 2 vols. (1907), 1:512–513. Vol 1 GL direct link Vol 2 GL direct link