God answered this question in Deuteronomy 18:10-22. If it comes to pass, then it is of God. If it does not come to pass do not fear the prophet that gave the word. He is not necessarily a false prophet, but you are not to fear him.
A prophet must always remember that he is merely the human being chosen to deliver a word from the Holy Spirit. He must not let his emotions enter his mind or be influenced by his flesh. It is easy for a prophet (because of his compassion) to want to see people healed, delivered, set free from poverty, etc. to presumptuously say, “God’s going to heal you!” That is only what the prophet wants to see happen. He does not have the authority to say anything unless he first hears the Holy Spirit say it. Even if the Holy Spirit revealed, through a Word of Knowledge to the prophet, a sickness a person may have, it is presumption to go ahead and say, “You are going to be healed.” Our carnal mind wants to say God is going to take care of this matter right now , but that is not always the way the Lord does it.
Once, the Lord had me prophesy to a person that he would have to wait for God to send him to another minister to receive his healing. This individual came to a service I was ministering at wearing a battery pack attached to his waist. It sent electrical shocks to his nerve endings in his back to keep them from dying while he recovered from major back surgery. This individual had worked for the electric company reading meters. His job required him to climb and jump over fences. The jarring of his back while completing these tasks had destroyed five vertebrae in his back. Doctors surgically placed two metal rods in his back and told him he would probably never walk again. I told him what the Lord had said – that He would send another minister to pray for him. However, my flesh desperately wanted to tell him that he was going to receive his healing that night! The kindest thing I could have done for him was to give him the word from the Lord exactly as I had received it.
Not long, about 6 weeks after I prophesied to him, he attended a meeting where Benny Hinn was ministering. Sure enough, someone prayed for him and he was healed. The man has had x-rays of his back made since the night he was prayed for and the metal rods are gone – they do not even show on the x-ray. He now works for Benny Hinn’s ministry and has had many opportunities to give his testimony of healing.
For more prophetic media groups click here