This question has puzzled theologians for ages, and has occasioned discussions which have had no profitable issue. There is no source of reliable information but that contained in Scripture and that is of a very meager character. See Rev. 12:7, 9, and II Peter 24. The inference from those and other passages is that Satan was created by God as man was, that he was pure and innocent, but, like man, liable to fall. That he did fall and was cast out of heaven. It cannot be conceived that God created an evil being, though, as we know to our sorrow, he did create a being who became evil. The whole subject is wrapped in mystery and the Bible writers are more intent on the practical question of teaching us how to be delivered from the power of Satan than in giving us his biography. The less we know of him and have to do with him the better for us. That Satan was an angel of high estate, who fell through ambition, leading to rebellion, is the concrete form of a history which is a combination of Scripture and tradition. See John 8-44; Matt. 4:1-11; Matt. 2541; Luke 8:12; Luke 10:18; Acts 13:10; Eph. 6:11; I Pet 5*; I John 3:8 and other passages. In Job he is the adversary and the tempter. See also I Chron. 21:1. Milton the poet described him as "the prince or ruler of the demons." See Dan. 7 :10 and Jude 6. These passages leave much unexplained and conjecture here is useless. His final overthrow and punishment are predicted in Rev. 20.