I think he doesn't. I mean his "kingdom" depends on how much unrest and strife he can bring to the world.
My husband and I were baptized together on Sunday. This was a big deal for us and our family. It meant a lot to us as believers in God. We were dipped in a pool of average, non-magical water, but came up as new creations of the Lord. It's probably a strange ritual to unbelievers, because although it has been blessed by a man of God, our awesome partor, it's still just regular water. The feeling can't be put into words to accurately describe the transformation, but it's real.
The devil must know it's real too and he doesn't like it. His desire is that "your thoughts will be led astray from a sincere and pure devotion to Christ." -2 Corinthians 11:3. And what could be more of an outward testament to that devotion to God than baptism? Right now, the devil is really mad at my household and he's coming after us.
Several small arguments have erupted in my house since Sunday (and yes today is only Tuesday), as well as a few trips down memory lane in the form of ex's crossing our paths. The devil is working overtime, with the hope of his paycheck being in the form of our downfall.
Despite these things, I feel strong, because I know that ultimately he will be defeated by my God. My God doesn't like when the devil messes with his children (like any awesome parent) and He will always have the last word.
So, in the meantime, I have to remember that victory is mine and "no weapon formed against me shall prosper" -Isaiah 54:7. The daily walk of striving to be Christ-like is filled with little traps of the world trying to seduce me to "have fun" and let loose; take a walk on the wild side. Then the wild side becomes the dark side, the devil's house. It's like a scary movie where the windows and doors are unable to be unlocked from inside; you're trapped (insert horror movie music and shuddering here).
Being kind to people and serving in church ministries and spending time with my family are my idea of fun. Being a Christian doesn't mean I'm boring or uptight, it means I have my priorities in order. It also doesn't mean that I don't make mistakes, argue with my husband, resist to forgive others, become jealous or angry, but it does mean that I'm human.
"...despite all these things, overwhelming victory is ours through Christ, who loved us" ~Romans 8:37.
So , I leave you with this last verse and hope that you too will fight against those things that threaten to separate you from God.