Agency (also referred to as free agency or moral agency), in the theology of The Church of Jesus Christ of Latter-day Saints (LDS Church), is "the privilege of choice which was introduced by God the Eternal Father to all of his spirit children in the premortal state". Mortal life is viewed as a test of faith, where our choices are central to the plan of salvation in Latter-day Saint teaching. "It was essential for their eternal progression that they be subjected to the influences of both good and evil". LDS Church members believe that Lucifer rebelled against the God's plan, which resulted in a war in heaven, and Lucifer being cast out of heaven and becoming Satan.