John 12:21b : Now the prince of this world will be cast out.
The Bible says that as a result of Jesus death, Satan was removed from all legal power over the world. Our sins were paid for. The Prince has no true subjects.
In C.S. Lewis’ “The Lion the Witch and the Wardrobe,” we see an allegory of this. If you remember, the stone table had written on it the deep magic which said that all breakers of what was written there belonged to the White Witch. Aslan the lion, chose to give up his life in place of the law breaker. Aslan resurrected and the stone table was broken, which completely destroyed the power that the witch had over lawbreakers. The White Witch was “cast out” of her place in Narnia.
Now, Satan, the Prince has no real authority to rule, but he plays the part. This reminds me of another movie: “Robin Hood Prince of Thieves”. Remember that the Sheriff of Nottingham was ruling the people illegally. When the real governor returned, Robin Hood was commended for fighting against the wicked Sheriff. It may not be that this was a real story of Robin Hood, but it certainly is an good picture of the Prince of this world and of those who appear as outlaws to go against the tide to fight him and his ways. It really is an impossible task for us to fight against a far superior evil power. The Spirit that God has given us is able to cause us to overcome in this world until Jesus returns:
1 John 4:4 : You are of God, little children, and have overcome them; because greater is he who is in you than he who is in the world.
The encouraging thing is that we know that Jesus has defeated the prince and will come back in the future to take His place as King.