The Great Controversy, by Ellen G. White, , at sacred-texts.com
The Lord has shown me that Satan was once an honored angel in heaven, next to Jesus Christ. His countenance was mild, expressive of happiness like the other angels. His forehead was high and broad, and showed great intelligence. His form was perfect. He had noble, majestic bearing. And I saw that when God said to his Son, Let us make man in our image, Satan was jealous of Jesus. He wished to be consulted concerning the formation of man. He was filled with envy, jealousy and hatred. He wished to be the highest in heaven, next to God, and receive the highest honors. Until this time all heaven was in order, harmony and perfect subjection to the government of God.
It was the highest sin to rebel against the order and will of God. All heaven seemed in commotion. The angels were marshaled in companies with a commanding angel at their head. All the angels were astir. Satan was insinuating against the government of God, ambitious to exalt himself, and unwilling to submit to the authority of Jesus. Some of the angels sympathized with Satan in his rebellion, and others strongly contended for the honor and wisdom of God in giving authority to his Son. And there was contention with the angels. Satan and his affected ones, who were striving to reform the government of God, wished to look into his unsearchable wisdom to ascertain his purpose in exalting Jesus, and endowing him with such unlimited power and command. They rebelled against the authority of the Son of God, and all the angels were summoned to appear before the Father, to have their cases decided. And it was decided that Satan should be expelled from heaven, and that the angels, all who joined with Satan in the rebellion, should be turned out with him. Then there was war in heaven. Angels were engaged in the battle; Satan wished to conquer the Son of God, and those who were submissive to his will. But the good and true angels prevailed, and Satan, with his followers, was driven from heaven.
After Satan was shut out of heaven, with those who fell with him, he realized that he had lost all the purity and glory of heaven forever. Then he repented and wished to be reinstated again in heaven. He was willing to take his proper place, or any place that might be assigned him. But no, heaven must not be placed in jeopardy. All heaven might be marred should he be taken back; for sin originated with him, and the seeds of rebellion were within him. Satan had obtained followers, those who sympathized with him in his rebellion. He and his followers repented, wept and implored to be taken back into the favor of God. But no, their sin, their hate, their envy and jealousy, had been so great that God could not blot it out. It must remain to receive its final punishment.
When Satan became fully conscious that there was no possibility of his being brought again into favor with God, then his malice and hatred began to be manifest. He consulted with his angels, and a plan was laid to still work against God's government. When Adam and Eve were placed in the beautiful garden, Satan was laying plans to destroy them. A consultation was held with his evil angels. In no way could this happy couple be deprived of their happiness if they obeyed God. Satan could not exercise his power upon them unless they should first disobey God, and forfeit his favor. They must devise some plan to lead them to disobedience that they might incur God's frown and be brought under the more direct influence of Satan and his angels. It was decided that Satan should assume another form, and manifest an interest for man. He must insinuate against God's truthfulness, create doubt whether God did mean as he said, next, excite their curiosity, and lead them to pry into the unsearchable plans of God, which Satan had been guilty of, and reason as to the cause of his restrictions in regard to the tree of knowledge.
See Isaiah 14:12-20; Ezekiel 28:1-19; Revelation 12:7-9