War in Heaven
From MormonWiki
The War in Heaven is the conflict that took place in the premortal life among the spirit children of God. Satan was cast out of heaven and into the earth, Rev. 12: 4, 7-9. The devil and a third part of heaven were thrust down, D&C 29: 36-37. Lucifer rebelled against the Only Begotten Son, D&C 76: 25-26. Satan sought the glory of the Father and to destroy the agency of man, Moses 4: 1-4 (Isa. 14: 12-15; Abr. 3: 27-28). Those who followed God kept their first estate, came to earth, and received bodies, Abr. 3: 26.