The Latter-day Saint doctrine regarding Lucifer comes from multiple sources. Many different scriptures, and doctrine taught in the temple, combine to paint a clear picture of his origins and intentions. Here, Lehi explains that he was "an angel of God." Other scriptures which teach of him are listed:
AND I, the Lord God, spake unto Moses, saying: That Satan, whom thou hast commanded in the name of mine Only Begotten, is the same which was from the beginning, and he came before me, saying--Behold, here am I, send me, I will be thy son, and I will redeem all mankind, that one soul shall not be lost, and surely I will do it; wherefore give me thine honor.
But, behold, my Beloved Son, which was my Beloved and Chosen from the beginning, said unto me--Father, thy will be done, and the glory be thine forever.
Wherefore, because that Satan rebelled against me, and sought to destroy the agency of man, which I, the Lord God, had given him, and also, that I should give unto him mine own power; by the power of mine Only Begotten, I caused that he should be cast down;
And he became Satan, yea, even the devil, 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 4:1-4)
And the Lord said: Whom shall I send? And one answered like unto the Son of Man: Here am I, send me. And another answered and said: Here am I, send me. And the Lord said: I will send the first.
And the second was angry, and kept not his first estate; and, at that day, many followed after him.(Abr 3:27-28)
And there was war in heaven: Michael and his angels fought against the dragon; and the dragon fought and his angels,
And prevailed not; neither was their place found any more in heaven.
And the great dragon was cast out, that old serpent, called the Devil, and Satan, which deceiveth the whole world: he was cast out into the earth, and his angels were cast out with him. (Rev 12:7-9)
And his tail drew the third part of the stars of heaven, and did cast them to the earth (Rev 12:4)
How art thou fallen from heaven, O Lucifer, son of the morning! how art thou cut down to the ground, which didst weaken the nations! For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God (Isa 14:12-13)