In His dealing with sin, God could employ only righteousness and truth. Satan could use what God could not—flattery and deceit. He had sought to falsify the word of God and had misrepresented His plan of government before the angels, claiming that God was not just in laying laws and rules upon the inhabitants of heaven; that in requiring submission and obedience from His creatures, He was seeking merely the exaltation of Himself. Therefore it must be demonstrated before the inhabitants of heaven, as well as of all the worlds, that God’s government was just, His law perfect. Satan had made it appear that he himself was seeking to promote the good of the universe. The true character of the usurper, and his real object, must be understood by all. He must have time to manifest himself by his wicked works. (GC 498.1) MC VC

The discord which his own course had caused in heaven, Satan charged upon the law and government of God. All evil he declared to be the result of the divine administration. He claimed that it was his own object to improve upon the statutes of Jehovah. Therefore it was necessary that he should demonstrate the nature of his claims, and show the working out of his proposed changes in the divine law. His own work must condemn him. Satan had claimed from the first that he was not in rebellion. The whole universe must see the deceiver unmasked. (GC 498.2) MC VC

Even when it was decided that he could no longer remain in heaven, Infinite Wisdom did not destroy Satan. Since the service of love can alone be acceptable to God, the allegiance of His creatures must rest upon a conviction of His justice and benevolence. The inhabitants of heaven and of other worlds, being unprepared to comprehend the nature or consequences of sin, could not then have seen the justice and mercy of God in the destruction of Satan. Had he been immediately blotted from existence, they would have served God from fear rather than from love. The influence of the deceiver would not have been fully destroyed, nor would the spirit of rebellion have been utterly eradicated. Evil must be permitted to come to maturity. For the good of the entire universe through ceaseless ages Satan must more fully develop his principles, that his charges against the divine government might be seen in their true light by all created beings, that the justice and mercy of God and the immutability of His law might forever be placed beyond all question. (GC 498.3) MC VC