God has told us through His prophets that we are free to choose between good and evil. We may choose liberty and eternal life by following Jesus Christ. We are also free to choose captivity and death by following Satan. (See 2 Nephi 2:27.) The right to choose between good and evil and to act for ourselves is called agency.

In our premortal life we had moral agency. One purpose of earth life is to show what choices we will make (see 2 Nephi 2:15–16). If we were forced to choose the right, we would not be able to show what we would choose for ourselves. Also, we are happier doing things when we have made our own choices.

Agency was one of the principal issues to arise in the premortal Council in Heaven. It was one of the main causes of the conflict between the followers of Christ and the followers of Satan. Satan said, “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” (Moses 4:1). In saying this, he “rebelled against [God] and sought to destroy the agency of man” (Moses 4:3). His offer was rejected, and he was cast out of heaven with his followers (see DC 29:36–37).