But as Celsus promises to give an account of the manner in which prophecies are delivered in Phœnicia and Palestine, speaking as though it were a matter with which he had a full and personal acquaintance, let us see what he has to say on the subject. First he lays it down that there are several kinds of prophecies, but he does not specify what they are; indeed, he could not do so, and the statement is a piece of pure ostentation. However, let us see what he considers the most perfect kind of prophecy among these nations.
“There are many,” he says, “who, although of no name, with the greatest facility and on the slightest occasion, whether within or without temples, assume the motions and gestures of inspired persons; while others do it in cities or among armies, for the purpose of attracting attention and exciting surprise. These are accustomed to say, each for himself, 'I am God; I am the Son of God; or, I am the Divine Spirit; I have come because the world is perishing, and you, O men, are perishing for your iniquities.
But I wish to save you, and you shall see me returning again with heavenly power. Blessed is he who now does me homage. On all the rest I will send down eternal fire, both on cities and on countries. And those who know not the punishments which await them shall repent and grieve in vain; while those who are faithful to me I will preserve eternally.'” Then he goes on to say: “To these promises are added strange, fanatical, and quite unintelligible words, of which no rational person can find the meaning: for so dark are they, as to have no meaning at all; but they give occasion to every fool or impostor to apply them to suit his own purposes.”
Source: Against Celsus (New Advent)