Gregory A. Boyd in his article "God At War" articulates very forcefully and clearly about the spiritual war that is going on.
The Old Testament clearly assumes that something profoundly sinister has entered God's creation and now perpetually threatens the world. Unlike all other warfare worldviews, the Old Testament repeatedly stresses the absolute supremacy of one God over all others and maintains unequivocally that this one God is never threatened by His enemies. This emphasis is a solid foundation for everything else the Lord subsequently reveals to humankind.
The period between the Old Testament and New Testament significantly transformed the Jewish worldview. From the time of the Exodus, the Jews had closely associated the truthfulness of their belief in Yahweh's supremacy with their political successes. His Lordship over Israel and over the entire world was, for them, most clearly evidenced by the fact that they had won, and preserved, independent status as a nation. The conviction that the cosmos is populated with good and evil spiritual beings - and that the earth is caught in the crossfire of their conflict - became centrally important for many Jews. So, the apocalyptic hope that Yahweh would soon vanquish Leviathan and all its cohorts grew in intensity during this intertestament period.
This intensification of Old Testament themes - this expansion and centralization of the Old Testament ideas about the lesser gods and Yahweh's conflicts with them - constitutes what has come to be called the apocalyptic worldview. If we are to understand the New Testament properly, we must read it against the backdrop of this worldview. The highest mediating agent of Yahweh has gone bad, abused his incredible God-given authority, taken the entire world hostage and set himself up as the illegitimate god of the present age. This spells disaster for the cosmos Fundamentally the mediating angelic authority structure - one that Yahweh set up at creation has gone bad at the very top. Because of this everything underneath this highest authority both in the heavens and on earth has been adversely affected. Vast multitudes of powerful angels having been given now authority over various aspects of creation or over lesser angels can now use this authority to wage war against God and against His people. It wasn't that all the angels had fallen, but in the minds of these writers, a great many of them had. Demons or the fallen angels could now freely infest this satanically governed world and work all manner of evil within it. What was to have been a godly council of heaven and a godly army for the Lord had turned itself into fierce rebel battalion which fought against God, in large part by terrorizing the earth and holding its inhabitants captive.
Most contemporary New Testament scholars believe it is primarily against this apocalyptic background that we are to understand the ministry of Jesus and the early church. His exorcisms, His healings and other miracles , as well as his work on the cross all remain to some extent incoherent and unrelated to one another until we interpret them within the apocalyptic context until we interpret them as acts of war. When this hermeneutical step is made, the ministry of Jesus forms a coherent whole.
As in apocalyptic thought, the assumption that Satan has illegitimately seized the world and thus now exercises a controlling influence over it, undergirds Jesus' entire ministry. Three times Jesus in John's gospel refers Satan as "the prince of this world"(Jn.12:31; 14:30; and 16:11). Jesus is saying that concerning powers that rule over the cosmos, this evil ruler is the highest.
When Satan claims that he can give all "authority and glory of all the kingdoms of the world" to whomever he wants because it all belongs to him, Jesus does not dispute him (Lk.4:5-6). Instead concurs with the apocalyptic worldview of His day-in agreement with John, Paul and the rest of the New Testament and believes the entire world is "under the power of the evil one". (1 Jn.5:19). and Satan is "the god of this world" (2 Cor.4:4) and "the ruler of the power of the air" (Eph.2:2). Jesus, therefore, concedes Satan's rulership of the earth. He will not, however, get back this worldwide kingdom by giving in to Satan's temptation and worshipping this illegitimate tyrant (Lk.4:7-8).
In keeping with the apocalyptic thought of His day, Jesus sees the evil tyrant as mediating and expanding his authority over the world through multitudes of demons that form a vast army under him. When Jesus was accused of casting out demons by the power of Beelzebul (another name for Satan), He responds by telling His hostile audience, "If a kingdom is divided against itself, that kingdom cannot stand" (Mk.3:24) This builds upon their shared assumption that the demonic kingdom is unified under one "prince" who is Satan. Jesus adds that one cannot make significant headway in taking back the "property" of this "kingdom" unless one first "ties up the strong man" who oversees the whole operation (Mk.3:27). This is what Jesus came to do. His whole ministry was about overpowering the "fully armed" strong man who guarded "his property" (Lk.11:21), namely God's people and ultimately the entire earth. Far from illustrating how Satan's kingdom works against itself, Jesus' success in casting out demons reveals that His whole ministry was about "tying up the strong man." This entire episode illustrates Jesus' assumption that Satan and demons form a unified kingdom. It is because of this assumption that Jesus refers to the "devil and his angels," implying that fallen angels belong to Satan. (Mt.25:41). And for the same reason, Jesus sees demonic activity as, by extension, the activity of Satan himself and judges everything done against demons as also done against Satan himself."
Jesus diagnoses a woman "with a spirit that had crippled her for eighteen years" as one whom "Satan bound" (Lk.13:11,16). Far from trying to discern some secret, sovereign, divine blueprint behind her grotesque deformity, He treats her as a casualty of war. The one ultimately responsible for her affliction, Jesus claims, was the captain of the opposing battalion himself. This does not mean that all sickness and decease is from Satan. When the disciples asked about the blind man as to who sinned, himself or his parents Jesus told them neither but that was to glorify God!
This is somewhat difficult for us to understand. Satan is the father of all lies and he is a usurper and even though Jesus did not dispute his claim during the temptation about Satan's claim that he is the ruler and owner of the whole world and its glory when the question of worship came up Jesus rebuked him and said that you have to worship God only. Jesus said that all power is given to me by my Father and he delegated all that power to us. Everything belongs to Him because He is the creator and preserver of the whole world. Everything was created by Him and for Him and He is the legitimate owner. Satan is a defeated enemy and he is destined for fire and eternal damnation. Until the final judgment day, the fight between good and evil, God and Satan will continue. The fact remains that by committing the first sin by Adam we lost the privilege of the fellowship and presence of God because the Glory of God left us. God was so kind and compassionate that He did not destroy Adam and Eve then and there and create another couple in their place. He made a provision for us to regain our position and restore us the original position of becoming His children by believing in Jesus. All that God demands from us is putting our faith in the finished work of Jesus. We cannot do anything or work for our salvation because it is the free gift of God. It is not because of our good works we are saved but by believing the Son of God who was sent to us by the heavenly Father that whosoever believes in Him will not perish but shall have everlasting life. We are not saved by our good works but we are saved to do good works.
Isaiah gives us a glimpse about the fall of Lucifer: "How you are fallen from heaven, O Lucifer, son of the morning! How you are cut down to the ground, You who weakened the nations! For you have said in your heart: I will ascend into heaven I will exalt my throne above the stars of God; I will also sit on the mount of the congregation on the farthest sides of the north; I will ascend above the heights of the clouds. I will be like the Most High . Yet you shall be brought down to Sheol to the lowest depths of the Pit. Those who see you will gaze at you, and consider you, saying, Is this the man who made the earth tremble, who shook kingdoms, who made the world as a wilderness and destroyed its cities, who did not open the house of his prisoners? (Is. 14:12 - 17). We know that a third of the angels in heaven joined him and were ready to wage war with Michael and the other two third angels on the other side. The rebellious angels with their leader Lucifer were thrown down from heaven. They are the fallen angels who are waging war with God. This is when the wrath of God is revealed in Genesis 1:2 when the earth became a chaotic waste and ruin. "For if God did not spare the angels who sinned, but cast them down to hell and delivered them into chains of darkness, to be reserved for judgment; (2 pt. 2:4).
"Let us always remember that we are at war. Until Jesus comes back and wins the final war and confines Satan and his army to the lake of fire we will continue to fight with the powers of darkness. Since Jesus defeated Satan and took away the keys of Hades and Death we know for sure that Jesus is holding our future. We need to trust God and not fear Satan or his evil powers any more. Jesus has already warned us that we need to be aware of his tactics. Peter warned us that the devil walks about like a roaring lion, seeking whom he may devour (1 Pt.5:8). Resist the devil and he will flee away. Every time a person is saved by the blood of Christ Satan loses him from his fold. We are plugged out of his garden and planted in the garden of God. There are only two groups of people in the world- the people of God and the people of the devil. If you have believed Jesus and accepted Him as your personal savior and Lord you are on God's side. There are only two powers in this world. Power of God or power of light and power of darkness. The fight between the powers of light and powers of darkness will continue until Jesus comes back and overpower the powers of darkness and confine them to the lake of fire. Thus says the Lord, the Holy One of Israel, and his Maker: "Ask Me of things to come concerning My sons, and concerning the work of My hands, you command Me. I have made the earth and created man on it. I - My hands - stretched out the heavens and all their host I have commanded. I have raised him up in righteousness and I will direct all his ways. (Is.43:11-13).
"I am God, and there is no other; I am God and there is none like Me, Declaring the end from the beginning and from ancient times things that are not yet done, saying, My counsel shall stand, and I will do all My pleasure". It is this God who has given us a mandate to preach the Gospel to all people groups of the world to take to them the good news that by believing in Jesus they can receive the free gift of salvation from the perishing state to eternal life. Jesus said that the thief (the devil) comes to kill and to destroy but "I have come that they may have life and that they may have it more abundantly". (Jn.10:10).
"How beautiful upon the mountains are the feet of him who brings good news, who proclaims peace, who brings glad tidings of good things, who proclaims salvation, who says to Zion, Your God reigns! (Is.52:7).
"Blessed be the God and Father of our Lord Jesus Christ, who according to His abundant mercy has begotten us again to a living hope through the resurrection of Jesus Christ from the dead, to an inheritance incorruptible and undefiled and that does not fade away, reserved in heaven for you, who are kept by the power of God through faith for salvation ready to be revealed in the last time.
You are a chosen generation, a royal priesthood, a holy nation, His own special people, that you may proclaim the praises of Him who called you out of darkness into His marvelous light. Therefore, be of one mind, having compassion for one another; love as brothers, be tenderhearted, be courteous; not returning evil for evil or reviling for reviling but on the contrary blessing, knowing that you were called to this that you may inherit a blessing. The eyes of the Lord are on the righteous and his ears are open to their prayers; but the face of the Lord is against those who do evil. Therefore, humble yourselves under the mighty hand of God, that He may exalt you in due time, casting all your care upon Him, for He cares for you.
If we walk in the light as He is in the light we have fellowship with one another and the blood of Jesus Christ cleanses us from all sin. Behold what manner of love the Father has bestowed on us, that we should be called children of God. (1 Jn.3:1)
We know that we are of God and the whole world lies under the sway of the wicked one. And we know that the Son of God has come and has given us an understanding, that we may know Him who is true; and we are in Him who is true, in His Son Jesus Christ. This is the true God and eternal life. (1 Jn.5:19-20).
In principle Jesus won the war, struck the decisive deathblow, vanquished Satan, restored humanity and established the kingdom. Yet some battles must still be fought before the ultimate victory is fully manifested. Because of this, Jesus did not just carry out His warfare ministry; He commissioned, equipped and empowered His disciples and later the whole of the church, to do the same. He set in motion the creation of a new humanity by giving us His power and authority to proclaim and demonstrate the Kingdom just the way He did
Therefore, if anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new. Now all things are of God, who has reconciled us to Himself through Jesus Christ, and has given us the ministry of reconciliation. Now then, we are ambassadors for Christ, as though God were pleading through us: we implore you on Christ's behalf, be reconciled to God. (2 Cor.5:17-20).
If you are reconciled to God and fellow men, why are you warring inside? Why do you engage in war of words with your companions and siblings? Why are you unable to forgive and forget? Why are you so intolerant?