Origen Against Celsus

Now, with regard to his statement that he "is acquainted with all our doctrines," we have to say that this is a boastful and daring assertion; for if he had read the prophets in particular, which are full of acknowledged difficulties, and of declarations that are obscure to the multitude, and if he had perused the parables of the Gospels, and the other writings of the law and of the Jewish history, and the utterances of the apostles, and had read them candidly.