of Spirit.

http://www.theempoweredchristian.com/of-spirit.html

“Jesus I know, and I know about Paul, but you, who are you?” - Acts 19:15. When some opportunist saw how much recognition was given to Paul after casting out demons, they tried to imitate in actions and words, but having not accepted the blood were “manhandled” by the very demons they tried to cast out. They were told that they were unrecognized which is referring to the Spirit of God and not their person. For all physical persons are known by demons but not having the right spirit, the demons did not acknowledge their authority over them.