Jewish and Christian scholars alike have both noted that the Old Testament view of God differs significantly from the New Testament view in one key aspect - the way Satan is viewed. The way Satan is viewed explains all discrepancies between the Old and New Testaments.
Let me explain
For the Old Testament believer, Satan was an obedient angel who had a tough job as God's enforcer who was in charge of
For sure, the New Testament confirms that Satan does engage in wrath, accusation, destruction, and temptation, but never under the approval or direction of God. The Old Testament says Satan is just following orders, while the New Testament says Satan is "off the grid" in complete disobedience to God.
In short, Old Testament saints see Satan as a Luca Brasi figure. Brasi was a character from “The Godfather” novel and movies who did the Godfather's dirty work, but who was absolutely loyal to his leader, perhaps even the most loyal. Brasi was an assassin, spy and fixer who always worked behind the scenes to discover and destroy those disloyal or opposed to his Godfather. He rooted out then disposed of the Godfather's enemies. He always had his Godfather's trust and blessing. This was the Old Testament view of Satan.
As The Encyclopedia of Jewish Concepts by Philip Birnbaum says, "Satan...is...identified with the angel of death. He leads astray, then he brings accusations against man, whom he slays eventually. His chief functions are those of temptation, accusation and punishment. Under the control of God, he acts solely with the divine permission to carry out his plots." (Sanhedrin Press, page 594).
Rabbi Benjamin Blech similarly writes, "Judaism sees Satan as a servant of God whose function is to set up choices between good and evil so that we can exercise our free will.... [His] apparent harshness is merely camouflage for divine concern and love." If God is So Good, Why is The World So Bad? (Simcha Press, pages 7-9)
Author Stephen Harris notes that the Old Testament Satan is not the same entity as the New Testament Satan. In the Old Testament, "The Satan figure acts as Yahweh's spy and prosecuting attorney whose job is to bring human misconduct to the deity's attention and, if possible, persuade Yahweh to punish it.
Throughout the Old Testament the Satan remains among the divine 'sons,' serves as God's administrative agent, and thus reveals a facet of the divine personality.... At the outset, some Bible writers saw all things, good and evil alike, as emanating from a single source - Yahweh. Israel's strict monotheistic credo decreed that Yahweh alone caused both joys and sorrows, prosperity and punishment (Deut. 28).... The canonical Hebrew Bible grants the Satan scant space and little power.
Whereas the Old Testament Satan can nothing without Yahweh's express permission, in the New Testament he behaves as an independent force who competes with the Creator for human souls.... According to Mark's Gospel, one of Jesus' major goals is to break up Satan's kingdom and the hold that he and lesser evil spirits exercise on the people. Hence, Mark stresses Jesus' works of exorcising devils and dispossessing the victims of demonic control. The New Testament, then-- in sharp contrast to the Old-- shows Satan and the devil as one, a focus of cosmic evil totally opposed to the Creator God. This 'evil one' is the origin of lies, sin, suffering, sickness and death." Understanding the Bible: A Reader’s Introduction, pages 26-28.
The renowned International Standard Bible Encyclopedia is in full agreement with this in its entry on Satan: "The Old Testament does not contain the fully developed doctrine of Satan found in the New Testament. It does not portray him as at the head of a kingdom, ruling over kindred natures and an apostate from the family of God.... It is a significant fact that the statements concerning Satan become numerous and definite only in the New Testament.
The daylight of the Christian revelation was necessary in order to uncover the lurking foe, dimly disclosed but by no means fully known in the earlier revelation.... In the early states of religious thinking it would seem to be difficult, if not impossible, to hold the sovereignty of God without attributing to His agency those evils in the world which are more or less directly connected with judgment and punishment.... The progressive revelation of God's character and purpose, which more and more imperatively demands that the origin of moral evil, and consequently natural evil, must be traced to the created will in opposition to the Divine, leads to the ultimate declaration that Satan is a morally fallen being to whose conquest the Divine Power in history is pledged."
Finally, scholar Jeffrey Burton Russell, who has written multiple volumes on the historical development of our understanding of Satan, notes that the reason early Jewish thought saw Satan as God's servant is as follows
"Since the God of Israel was the only God, the supreme power in the cosmos, and since, unlike the abstract God of the Greeks, He had personality and will, no deed could be done unless He willed it. Consequently, when anyone transgressed morality, God was responsible for the transgression as well as for its punishment." The Prince of Darkness: Radical Evil and the Power of God in History, (Cornell University Press, 29-30)
Russell goes on to trace that later in Jewish history, closer to Jesus' day, more and more Jews began to see Satan as an evil entity acting independently of God's approval. This is easily proven by considering the incident in which King David sinned by numbering Israel. This incident is first recorded in 2 Samuel 24:1, and then centuries later in 1 Chronicles 21:1.
In the earlier entry, David's sin is caused by "the anger of God," while in the later passage "Satan" is the cause of David's sin. Same sin, same event, entirely different cause. The Jews were beginning to see that they could not attribute both sin and punishment to God, good and evil to God, love and hate to God. They began to develop the idea that Satan was an enemy to God's purposes rather than an obedient friend. Unfortunately, when Israel as a nation rejected Jesus as Messiah, they also rejected the truth about Satan and have since sadly regressed back to their early Old Testament view, as the earlier quotes above show.
But let's catch our breath and think about this for a moment. If in the passage above, Satan's destructive activity is wrongly attributed as God's wrath, then where does that leave us?
It leaves us falsely accusing God of all sorts of evil events, motives and destructions. We have chained God and Satan at the spiritual hip, good and evil at the spiritual hip, love and wrath at the spiritual hip - God is blamed for all that Satan does, while Satan gets partial credit for the good God does. The end result is that the character of God is clouded and men are unable to fully see, trust and rejoice in his love and forgiveness.
So was the Old Testament view of Satan different than the New Testament view?
Yes, vastly different, but perhaps the best way to put it is not so much that the Old Testament was wrong about Satan, but that the Old Testament was almost completely uninformed about him. The first reference to Satan is not even until 548 pages into the Old Testament. Satan is first mentioned only 3 pages into the New Testament. The total number of times Satan is mentioned in the Old Testament is 19 times, 14 of which are in the book of Job. The New Testament mentions Satan (or his devils) nearly 200 times, despite the fact that it is five times shorter than the Old Testament in length.
Only three Old Testament writers ever even mention Satan, and that only briefly. Every New Testament writer mentions Satan. Amazingly, Moses, David, Abraham and Solomon never mentioned Satan at all.
Their clueless silence is hard to imagine, given the fact that these men are considered giants of the faith. Contrast this with the New Testament, where Jesus repeatedly calls Satan "the ruler of this world" (John 12:31; 14:30; 16:11), the Apostle Paul calls Satan "the god of this world" (2 Corinthians 4:4) and "the prince of the power of the air" (Ephesians 2:2) who can appear as "an angel of light" (2 Corinthians 11:14). The Apostle Peter calls Satan "your adversary... a roaring lion, seeking whom he may devour" (1 Peter 5:8), and the Apostle John calls Satan "the evil one... in whose power the whole world lies." (1 John 5:19).
What is going on here?
Not one Old Testament verse warns us of Satan's evil influence in our hearts or minds, much less his rebellious rule over the entire fallen world. Not one demon is cast out in the Old Testament. Legions of devils are cast out in the New Testament. Evil spirits are sent from the Lord in the Old Testament (1 Samuel 16:14), but are sent from Satan as Beezlebub, the ruler of demons, in the New Testament (Matthew 12:24-29).
Jesus' main thrust in ministry was to destroy the works of Satan, not enable them or approve of them in any way. "He who sins is of the devil, for the devil has sinned from the beginning. For this purpose the Son of God was manifested, that He might destroy the works of the devil." (1 John 3:8)
When summarizing the Gospel for the first Gentile converts, Peter described "how God anointed Jesus of Nazareth with the Holy Ghost and with power, who went about doing good and healing all who were oppressed of the devil; for God was with Him." Acts 10:38.
Jesus continually exposed Satan as an enemy of His Father, and not a servant. Jesus described Satan as: "a murderer from the beginning, and does not stand in the truth, because there is no truth in him. When he speaks a lie he speaks from his own resources, for he is a liar and the father of it." (John 8:44)
This is a crucial passage for it shows Satan's evils come from "his own resources," not God's, and that he is in essence a killer and a liar, in fact the "father" of all killing and lying. Remember, Satan tried to both deceive and kill Jesus in the wilderness temptations in Luke 4. Jesus defeated him then and went on defeating him throughout the rest of Jesus' life, death and resurrection.
Jesus not only opposed Satan personally, he fought against Satan's entire kingdom of demonic elements, "against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places." Ephesians 6:10. Through the work of the cross, Jesus defeated all of Satan's armies, "Having disarmed principalities and powers, He made a public spectacle of them, triumphing over them in it." (Colossians 2:15) Greek scholars tell us these words describe Jesus having a victory parade wherein He brandishes all the captured armor of Satan's kingdom for all to see and celebrate. Satanic captivity has been taken captive by the Lord of love and light who has ransomed and rescued us from our dark kidnappers.
Now we see what one of the main problems was with Old Testament believers. They simply did not have the depth of understanding to see the truth about God's Kingdom as it related to Satan's kingdom. Their understanding of what we call New Covenant truth was at most only embryonic. This is the perfect example of John Calvin's claim that Old Testament saints had only "sleight capacity" to understand deeper New Testament concepts - the true nature of Satan being just such a concept.
Without the indwelling Holy Spirit to lead them into all truth, Old Testament saints simply could not accurately process how the two invisible personalities of God and Satan operated on the earth. It wasn't God working with Satan as they supposed. It was God working against Satan as Jesus revealed.
Jesus revealed that between their two kingdoms, there was no treaty, no cooperation, no partnership, no under-the-table deals, no compromise, no joint operation going on. It was war!
Jesus stated the battle lines of this war in John 10:10, "The thief does not come except to steal, and to kill, and to destroy. But I have come that they may have life, and have it more abundantly."
Satan = stealing, killing, destroying.
Jesus = life abundant.