The devil knows that his Master and Lord has given disciples (men and women of faith) authority over all of his power.
He knows that the Promise of the Father, the infilling of the same Power that raised Christ from the dead, is the present inheritance of every one who believes.
The devil knows that Jesus came to destroy his works, e.g., sin, sickness, torment and death. That Jesus sent His followers out to do exactly what the Father sent Him to do.
The devil knows that Jesus would not dispatch His Body to advance His Kingdom without giving them the very means and methods He, Himself, used to establish it.
The devil knows that a man or woman who wears the Name of Christ, can do what ordinary men cannot. Indeed, believers can do the miraculous works Jesus declared they would do because He is always with them.
The devil knows that the faith of most believers restricts them from acting out these realities in any practical way.
The devil works like hell to keep it so.