Vain is defined as “empty; worthless; having no substance, value or importance. … Elated with a high opinion of one’s own accomplishments” (Noah Webster’s First Edition of an American Dictionary of the English Language, 1828 [1967]).
Elder Dallin H. Oaks of the Quorum of the Twelve Apostles counseled Latter-day Saints to avoid becoming preoccupied with the vain things of the world: “Jesus taught that ‘a man’s life consisteth not in the abundance of the things which he possesseth’ (Luke 12:15). Consequently, we should not lay up for ourselves ‘treasures upon earth, where moth and rust doth corrupt, and where thieves break through and steal’ (Matthew 6:19). In other words, the treasures of our hearts—our priorities—should not be what the scriptures call ‘riches [and] the vain things of this world’ (Alma 39:14). The ‘vain things of [the] world’ include every combination of that worldly quartet of property, pride, prominence, and power. As to all of these, the scriptures remind us that ‘you cannot carry them with you’ (Alma 39:14). We should be seeking the kind of treasures the scriptures promise the faithful: ‘great treasures of knowledge, even hidden treasures’ (D&C 89:19)” (in Conference Report, Apr. 2001, 109; or Ensign, May 2001, 84).
Elder Jeffrey R. Holland also noted that vanity of physical appearance is spiritually dangerous: “In terms of preoccupation with self and a fixation on the physical, this is more than social insanity; it is spiritually destructive and it accounts for much of the unhappiness … in the modern world. And if adults are preoccupied with appearance—tucking and nipping and implanting and remodeling everything that can be remodeled—those pressures and anxieties will certainly seep through to children. At some point the problem becomes what the Book of Mormon called ‘vain imaginations’ [1 Nephi 12:18]. And in secular society both vanity and imagination run wild. One would truly need a great and spacious makeup kit to compete with beauty as portrayed in media all around us” (in Conference Report, Oct. 2005, 30–31; or Ensign, Nov. 2005, 30).