Our Father who art in heaven,
Hallowed be Thy name.
Thy kingdom come, Thy will be done
On earth as it is in heaven.
Give us this day our daily bread
And forgive us our debts
As we forgive our debtors.
And lead us not into temptation,
But deliver us from evil.
This may be the most important part of the prayer. All of the newer translations agree that this should read, “but deliver us from the evil one,” so that tells us there is some level of personification there in the original language. The gist of what is being said here for us, then, is basically, “Lead us not into temptation, but deliver us from the evil one who is behind it all.”
Satan is not like God — he cannot be everywhere at once — but he has a host of minions — angels who have fallen from heaven and joined his team. They are called demons. Sometimes they possess a person, mostly they try to influence believers to get them to doubt and turn away from the Lord. They don’t have to spend much time working on those who have given into temptation and the pride and idolatry all around us. They are already in the grip of evil. They are mostly trying to distract believers and render us ineffective in our service for the Lord. (See Screwtape Letters, by C.S. Lewis).
Recalling our recent study on spiritual warfare, most of what goes on here is beyond us. We are talking about spiritual realms in other dimensions. That’s why we must rely on prayer, because these things are beyond our control.
Once again, I must reiterate, this struggle with evil is real. These are not Sunday school games. Jesus wants us to pray to be delivered from the evil one because “your great enemy, the devil prowls around like a roaring lion, looking for someone to devour” (1 Peter 5:8).
Some might wonder why God allows for all this to go on. Why are we constantly in battle? Why doesn’t God spare us from all this? Isn’t He God? Can’t He do that? Well yes, He could; He can do anything He wants; but He doesn’t, because He has something in mind for us in the battle. He doesn’t want to take us out of the battle, He wants to bring us through the battle, and we probably won’t know the reasons for this until much later.
Like Dorothy Sayers observed: “What do we find God doing about this business of sin and evil? God did not abolish the fact of evil; He transformed it. He did not stop the Crucifixion; He rose from the dead.” He wants to bring us through in the same exciting way. So keep praying: “but deliver us from evil,” because God wants you coming through, in a big way, with Him.
So keep praying, “deliver us from the evil one.” Satan or his minions cannot touch you if you pray. Greater is He that is in you than he that is in the world.
John Fischer The Catch 
God wants to bring us through the battle so that we can be sanctified since we, through original sin committed by the first Adam, brought the spiritual battle on ourselves.
Simply, God’s perfect justice requires that we participate in our own battle He cannot hand us His victory because our sin nature would not be defeated. Instead, he provides us with an opportunity through the second Adam to choose to be saved from our sin nature.
As we mature in Christ, He provides us with the opportunity to acknowledge the need to put on His armor as Christian soldiers and to join Him in the battle against the evil one and his demons. We do this by standing firm against principalities and strongholds so that almighty God already victorious can finish the war.
At the same time, we as His soldiers so armed can continue to bring others to the foot of the cross so that they might choose salvation. Thereupon, we baptize them in the name of the Father and the Son and the Holy Spirit, arming them with the Word, strengthening them in prayer and Fellowship, and leading them into battle for God’s kingdom. Amen and amen!
Yea, Gary! And to that I add another “Amen!”