It takes a sharp discerning eye to detect a false prophet because they have been uniquely designed to deceive the faithful. We are afterall "at war" with powers and principalities. How can it be possible for the faithful to be deceived? That is a simple answer, if we choose to be in a lukewarm relationship with the Lord. There is no possible way for anyone to be deceived by a false prophet or any other false gift or office if one is indeed walking closely with the Lord. The Spirit of God will never allow you to be deceived, in fact, He will lead and guide you into all truth and righteousness.