In Mormon doctrine, Satan, also known as Lucifer, is a spirit son of God. He was with us in the pre-mortal life and had great influence over those around him. He is sometimes referred to as a “Son of the Morning,” which could refer to the time of his spiritual creation by God the Father, or to his superior intelligence, which would be trumped by his irrepressible pride.
He fell. As Isaiah 14:12 states, he proposed a plan that would take away man’s agency, which is an eternal principle valued and consistently upheld by God. He desired glory and power. To get it, he sought to force all men to keep the commandments of God. His way was to use compulsion or force to “save” every person, and, for doing so, he demanded the glory and honor of God. Unlike Lucifer’s proposition, the Lord’s plan allowed individuals to progress, through the opportunity to choose between good and evil. When Satan’s plan was refused, he became angry and turned in open rebellion against God. His arguments were so convincing that one third of all of Heavenly Father’s spirit children followed after Satan (see Doctrine and Covenants 29: 36; Moses 4: 1-4; Abraham 3: 27-28).
Lucifer and his followers were cast out of heaven and denied ever having mortal bodies. They are spiritually dead, meaning they are eternally cut off from the presence of God.
Now Satan and his followers work to thwart Heavenly Father’s plan and lead His children to sin and their own spiritual deaths (see Revelation 12: 9; 2 Nephi 2: 27; 9: 8-9).
Satan is the enemy of God’s will and all that is good and righteous. He is the father of all lies and the inspiration for all that is evil. But his opposition to God allows mankind the very real choice between good and evil.
Mormon Church leaders continually remind us that Satan is a real, literal being whose lies and snares must be avoided through righteousness.
Is Satan the Brother of Jesus?
Mormons are often accused of following this strange doctrine, which sounds appalling to those unfamiliar with the Plan of Salvation. The true plan of salvation, revealed through the prophets, explains that we existed before we were born to earthly parents as physical, mortal beings. In the Pre-Mortal life, we lived as spiritual children of our Father in Heaven. In order to progress to become like Him, we had to first gain mortal bodies, dwell in faith on an earth full of trial, and then be resurrected and exalted. In the Pre-Mortal life, Christ was the first-born of the Father and the one chosen to save us from our sins and shortcomings. Father’s plan included the exercise of our free-agency, the opportunity to choose between good and evil, which necessitated opposition in all things. Satan was also a spirit-child of God, one with superior intelligence, who rebelled and became the enemy of all things good and righteous. Thus, we were all brothers and sisters in the Pre-Mortal world, as were Satan and Jesus Christ. Mormons often call Jesus Christ “our Elder Brother.”