19 For it was the Father’s good pleasure for all the fullness to dwell in Him,
20 and through Him to reconcile all things to Himself, having made peace through the blood of His cross; through Him, I say, whether things on earth or things in heaven.
Colossians 1:19-20
When Jesus came to us, as flesh and blood, he came to destroy the works of the devil. Through our own human frailty we gave in to our temptation of wanting to be gods and brought sin into the garden of Eden. Adam and Eve allowed themselves to be seduced by evil. Our western reasoning would like for us to believe that evil is merely a metaphor for bad things we can't explain. In actuality, evil is a living spiritual being that perverts creation. Evil uses sin to bring perversion to the human free will and to turn us away from God.
Evil (demonic oppression) enters by invitation.
Very bad things can happen to people to put them into a condition of unforgiveness with a painfully wounded soul. Jesus came to heal the broken hearted and to set free those imprisoned by their soul wounds. He heals through the power of his name, his grace and his mercy.
Evil can also enter through a life void of God. Demonic oppression just doesn't happen overnight. Many times it is people's life styles that is opening them up to demonic oppression.
Jesus was the first deliverance minister, he healed people both physically and spiritually. Jesus alone had the authority and the power over satan. Jesus passed the authority on to the apostles and to us. The Roman Catholic church makes a distinction between deliverance ministry and the rite of exorcism. The rite of exorcism is specifically reserved for ordained and specially trained Roman Catholic priests. For non-Roman Catholic pastors, deliverance ministry is the same thing. Accomplishes the same end result, only we don't use the Rite. The deliverance ministry of Jesus is the healing of the soul of a person by expelling oppressing (or even possessing) demons and closing open doorways of their entry.
26 Otherwise, He would have needed to suffer often since the foundation of the world; but now once at the consummation of the ages He has been manifested to put away sin by the sacrifice of Himself.
Hebrews 9:26
Jesus was the ultimate sacrifice for you and me in this spiritual war. Through him we are given everlasting life and no longer have the fear of death. Fear, and unforgiveness are the weapons of satan. Through fear the enemy can convince you your life isn't worth living, or keep you in your own prison of fear of everything, or even cause demonic manifestations. Through Jesus and his work on the cross you can be restored and set free from a life of slavery to fear.
13 When you were dead in your transgressions and the uncircumcision of your flesh, He made you alive together with Him, having forgiven us all our transgressions,
14 having canceled out the certificate of debt consisting of decrees against us, which was hostile to us; and He has taken it out of the way, having nailed it to the cross.
15 When He had disarmed the rulers and authorities, He made a public display of them, having triumphed over them through Him.
Colossians 2:13-15
Jesus won the battle at the cross. This set in motion the clock for satan and his demon's final judgement. They lost the war, but are permitted to roam until Jesus returns in the end times. At this time, that only God knows, satan and his demons will be stripped of power and punished in the lake of fire.
10 And the devil who deceived them was thrown into the lake of fire and brimstone, where the beast and the false prophet are also; and they will be tormented day and night forever and ever.
Revelation 20:10
Because the spirits roam the earth they can still torment people. Demons hate people! They want to destroy all of us, including the people that worship them. God didn't leave us empty handed in this spiritual war. Jesus Christ, the one true God, left us with authority over the demonic. Authority that drives demons out of people and houses, -and tells them to never return.