Quotes about prophecy from throughout Christian History.
The most admirable Polycarp, when he first heard [that the authorities were looking for him], was not in the least disturbed, but resolved to stay in the city. However, in deference to the wish of many, he was persuaded to leave it. He departed, therefore, to a country house not far from the city. There he stayed with a few [friends], engaged in nothing else night and day than praying for everyone and for the Churches throughout the world, according to his usual custom. And while he was praying, a vision presented itself to him three days before he was taken; and, behold, the pillow under his head seemed to him on fire. Upon this, turning to those that were with him, he said to them prophetically, "I must be burnt alive." (Martyrdom of Polycarp 5)
"How then, sir," I asked, "will a man know which of them is the prophet and which the false prophet?"
"I will tell you," says [the Angel of Repentance], "about both the prophets, and then you can try the true and the false prophet according to my directions. Try the man who has the Divine Spirit by his life. First, he who has the Divine Spirit proceeding from above is meek, peaceful, humble, and refrains from all iniquity and the vain desire of this world. He contents himself with fewer wants than those of other men, and when asked makes no reply. Nor does he speak privately, nor when someone wishes the Spirit to speak does the Holy Spirit speak, but he speaks only when God wishes him to speak. When, then, a man having the Divine Spirit comes into an assembly of righteous men who have faith in the Divine Spirit, and this assembly of men offers up prayers to God, then the angel of the prophetic Spirit, who is destined for him, fills the man. The man, being filled with the Holy Spirit, speaks to the multitude as the Lord wishes. Thus, then, will the Spirit of Divinity become manifest. Whatever power comes from the Spirit of Divinity belongs to the Lord.
... "Hear then," says he, "in regard to the spirit which is earthly, empty, powerless, and foolish. First, the man who seems to have the Spirit exalts himself, wishes to have the first seat, is bold and impudent, talkative, and lives in the midst of many luxuries and many other delusions, and takes rewards for his prophecy. If he does not receive rewards, he does not prophesy. Can, then, the Divine Spirit take rewards and prophesy? It is not possible that the prophet of God should do this, but the prophets of this character are possessed by an earthly spirit. Then it never approaches an assembly of righteous men, but shuns them. It associates with doubters and the vain. It prophesies to them in a corner and deceives them, speaking to them according to their desires, mere empty words, for they are empty to whom it gives its answers. ...
When ... it comes into an assembly of righteous men who have the Spirit of Divinity, and the offer up prayer, that man is made empty, and the earthly spirit flees from him through fear, and that man is made dumb and is entirely crushed, being unable to speak. ... So also the empty prophets, when they come to the spirits of the righteous, are found to be such as they were when they came.
This, then, is the mode of life of both prophets. Try by his deeds and his lef the man who says he is inspired. As for you, trust the Spirit which comes from God and has power, but the spirit which is earthly and empty do not trust at all, for there is no power in it. It comes from the devil. (Shepherd of Hermas. Commandment XI.)