I must express my surprise that Celsus should class the Odrysians, and Samothracians, and Eleusinians, and Hyperboreans among the most ancient and learned nations, and should not deem the Jews worthy of a place among such, either for their learning or their antiquity, although there are many treatises in circulation among the Egyptians, and Phœnicians, and Greeks, which testify to their existence as an ancient people, but which I have considered it unnecessary to quote. For any one who chooses may read what Flavius Josephus has recorded in his two books, On the Antiquity of the Jews, where he brings together a great collection of writers, who bear witness to the antiquity of the Jewish people; and there exists the Discourse to the Greeks of Tatian the younger, in which with very great learning he enumerates those historians who have treated of the antiquity of the Jewish nation and of Moses.
It seems, then, to be not from a love of truth, but from a spirit of hatred, that Celsus makes these statements, his object being to asperse the origin of Christianity, which is connected with Judaism. Nay, he styles the Galactophagi of Homer, and the Druids of the Gauls, and the Getæ, most learned and ancient tribes, on account of the resemblance between their traditions and those of the Jews, although I know not whether any of their histories survive; but the Hebrews alone, as far as in him lies, he deprives of the honour both of antiquity and learning.
And again, when making a list of ancient and learned men who have conferred benefits upon their contemporaries (by their deeds), and upon posterity by their writings, he excluded Moses from the number; while of Linus, to whom Celsus assigns a foremost place in his list, there exists neither laws nor discourses which produced a change for the better among any tribes; whereas a whole nation, dispersed throughout the entire world, obey the laws of Moses. Consider, then, whether it is not from open malevolence that he has expelled Moses from his catalogue of learned men, while asserting that Linus, and Musæus, and Orpheus, and Pherecydes, and the Persian Zoroaster, and Pythagoras, discussed these topics, and that their opinions were deposited in books, and have thus been preserved down to the present time.
And it is intentionally also that he has omitted to take notice of the myth, embellished chiefly by Orpheus, in which the gods are described as affected by human weaknesses and passions.
Source: Against Celsus (New Advent)