“The Only True and Living Church upon the Face of the Whole Earth”

Doctrine and Covenants 1:29–30

29 And after having received the record of the Nephites, yea, even my servant Joseph Smith, Jun., might have power to translate through the mercy of God, by the power of God, the Book of Mormon.
30 And also those to whom these commandments were given, might have power to lay the foundation of this church, and to bring it forth out of obscurity and out of darkness, the only true and living church upon the face of the whole earth, with which I, the Lord, am well pleased, speaking unto the church collectively and not individually . . .

President Boyd K. Packer said:

“The position that The Church of Jesus Christ of Latter-day Saints is the only true Church upon the face of the earth is fundamental. . . . Now to those who think us uncharitable, we say that it was not devised by us; it was declared by Him [in D&C 1:30]. . . . Now this is not to say that the churches, all of them, are without some truth. They have some truth—some of them very much of it. They have a form of godliness. Often the clergy and adherents are not without dedication, and many of them practice remarkably well the virtues of Christianity. They are, nonetheless, incomplete. By His declaration, ‘they teach for doctrines the commandments of men, having a form of godliness, but they deny the power thereof’ (Joseph Smith—History 1:19).”

(“The Only True and Living Church,” Ensign, Dec. 1971, 40.)