The devil is already defeated
The Bible tells us, “God hath not given us the spirit of fear” (2 Timothy 1:7). The devil is our adversary, according to 1 Peter 5:8, and he goes around seeking whom he may devour. God tells us in the same verse that we are to be watchful and stay alert, so we are not victimized by him. John 10:10 tells us that the thief comes only to steal, kill and destroy.