2 Nephi 2:14
14 And now, my sons, I speak unto you these things for your
profit and learning; for there is a God, and he hath created all
things, both the heavens and the earth, and all things that in
them are, both things to act and things to be acted upon.

2 Nephi 2:15
15 And to bring about his eternal purposes in the end of man,
after he had created our first parents, and the beasts of the
field and the fowls of the air, and in fine, all things which are
created, it must needs be that there was an opposition; even the
forbidden fruit in opposition to the tree of life; the one being
sweet and the other bitter.

2 Nephi 2:16
16 Wherefore, the Lord God gave unto man that he should act for
himself. Wherefore, man could not act for himself save it should
be that he was enticed by the one or the other.

2 Nephi 2:17
17 And I, Lehi, according to the things which I have read, must
needs suppose that an angel of God, according to that which is
written, had fallen from heaven; wherefore, he became a devil,
having sought that which was evil before God.

2 Nephi 2:18
18 And because he had fallen from heaven, and had become
miserable forever, he sought also the misery of all mankind.
Wherefore, he said unto Eve, yea, even that old serpent, who is
the devil, who is the father of all lies, wherefore he said: