73 But are we alone in this position? What! Have you not introduced into the number of your gods the Egyptian deities named Serapis and Isis, since the consulship of Piso and Gabinius? What! Did you not begin both to know and be acquainted with, and to worship with remarkable honours, the Phrygian mother— who, it is said, was first set up as a goddess by Midas or Dardanus— when Hannibal, the Carthaginian, was plundering Italy and aiming at the empire of the world? Are not the sacred rites of mother Ceres, which were adopted but a little while ago, called Graeca because they were unknown to you, their name bearing witness to their novelty?
Is it not said in the writings of the learned, that the rituals of Numa Pompilius do not contain the name of Apollo? Now it is clear and manifest from this, that he, too, was unknown to you. but that at some time afterwards he began to be known also. If any one, therefore, should ask you why you have so lately begun to worship those deities whom we mentioned just now, it is certain that you will reply, either because we were C lately not aware that they were gods, or because we have now been warned by the seers, or because, in very trying circumstances, we have been preserved by their favour and help.
But if you think that this is well said by you, you must consider that, on our part, a similar reply has been made. Our religion has sprung up just now; for now He has arrived who was sent to declare it to us, to bring us to its truth; to show what God is; to summon us from mere conjectures, to His worship.
Source: Against the Heathen (New Advent)