SATAN: OLD TESTAMENT SERVANT ANGEL OR NEW TESTAMENT COSMIC REBEL?
The problem is one of definition and differentiation. The Old Testament saints had a largely UNDIFFERENTIATED view of God and Satan. They believed Satan was God's "left hand," His "angry voice," His official "minister of wrath."
Old Testament saints wrongly included Satan in their functional definition of God. Whenever there was temptation, destruction, wrath, and death, all activities which the New Testament would later assign to Satan, the Old Testament would instead attribute these destructions to God Himself. They would not pray against the wiles of the devil, the way the New Testament instructs, but would rather beg God to stay His own wrathful hand. Satan was nowhere in their causative equation. God was the ONLY cause of both good and evil.
The New Testament, by contrast, DIFFERENTIATES the identities of God and Satan totally. What is joined at the conceptual hip in the Old Testament is separated and forever severed in the New. Jesus, it could be argued, IS the DYNAMIC DIFFERENTIATION of God's image from Satan's image. He is the refining fire which burns all the unworthy attributes the Old Testament God out and away from the pure and perfect divine nature.