Let us notice the charges which are next advanced by Celsus, in which there is exceedingly little that has reference to the Christians, as most of them refer to the Jews. His words are: “If, then, in these respects the Jews were carefully to preserve their own law, they are not to be blamed for so doing, but those persons rather who have forsaken their own usages, and adopted those of the Jews. And if they pride themselves on it, as being possessed of superior wisdom, and keep aloof from intercourse with others, as not being equally pure with themselves, they have already heard that their doctrine concerning heaven is not peculiar to them, but, to pass by all others, is one which has long ago been received by the Persians, as Herodotus somewhere mentions. 'For they have a custom,' he says, 'of going up to the tops of the mountains, and of offering sacrifices to Jupiter, giving the name of Jupiter to the whole circle of the heavens.' And I think,” continues Celsus, “that it makes no difference whether you call the highest being Zeus, or Zen, or Adonai, or Sabaoth, or Ammoun like the Egyptians, or Pappæus like the Scythians. Nor would they be deemed at all holier than others in this respect, that they observe the rite of circumcision, for this was done by the Egyptians and Colchians before them; nor because they abstain from swine's flesh, for the Egyptians practised abstinence not only from it, but from the flesh of goats, and sheep, and oxen, and fishes as well; while Pythagoras and his disciples do not eat beans, nor anything that contains life. It is not probable, however, that they enjoy God's favour, or are loved by Him differently from others, or that angels were sent from heaven to them alone, as if they had had allotted to them 'some region of the blessed,' for we see both themselves and the country of which they were deemed worthy. Let this band, then, take its departure, after paying the penalty of its vaunting, not having a knowledge of the great God, but being led away and deceived by the artifices of Moses, having become his pupil to no good end.”
Source: Against Celsus (New Advent)