Whereas the Lord is “a God of truth, and canst not lie” (Ether 3:12), Satan “was a liar from the beginning” (D&C 93:25). The Lord revealed to Moses that “Satan, yea, even the devil, [is] the father of all lies, to deceive and to blind men, and to lead them captive at his will, even as many as would not hearken unto my voice” (Moses 4:4).
Elder Dallin H. Oaks of the Quorum of the Twelve Apostles explained that Satan “and the spirits who follow him are still deceiving the world. … Satan’s methods of deception are enticing: music, movies and other media, and the glitter of a good time. When Satan’s lies succeed in deceiving us, we become vulnerable to his power” (in Conference Report, Oct. 2004, 46; or Ensign, Nov. 2004, 43).