He next represents Christians as saying what he never heard from any Christian; or if he did, it must have been from one of the most ignorant and lawless of the people. “Behold,” they are made to say, “I go up to a statue of Jupiter or Apollo, or some other god: I revile it, and beat it, yet it takes no vengeance on me.” He is not aware that among the prohibitions of the divine law is this, “You shall not revile the gods,” and this is intended to prevent the formation of the habit of reviling any one whatever; for we have been taught, “Bless, and curse not,” and it is said that “revilers shall not inherit the kingdom of God.” And who among us is so foolish as to speak in the way Celsus describes, and to fail to see that such contemptuous language can be of no avail for removing prevailing notions about the gods?
For it is matter of observation that there are men who utterly deny the existence of a God or of an overruling providence, and who by their impious and destructive teaching have founded sects among those who are called philosophers, and yet neither they themselves, nor those who have embraced their opinions, have suffered any of those things which mankind generally account evils: they are both strong in body and rich in possessions. And yet if we ask what loss they have sustained, we shall find that they have suffered the most certain injury.
For what greater injury can befall a man than that he should be unable amidst the order of the world to see Him who has made it? And what sorer affliction can come to any one than that blindness of mind which prevents him from seeing the Creator and Father of every soul?
Source: Against Celsus (New Advent)