And the charge of folly applies not only to those who offer prayers to images, but also to such as pretend to do so in compliance with the example of the multitude: and to this class belong the Peripatetic philosophers and the followers of Epicurus and Democritus. For there is no falsehood or pretence in the soul which is possessed with true piety towards God. Another reason also why we abstain from doing honour to images, is that we may give no support to the notion that the images are gods.
It is on this ground that we condemn Celsus, and all others who, while admitting that they are not gods, yet, with the reputation of being wise men, render to them what passes for homage. In this way they lead into sin the multitude who follow their example, and who worship these images not simply out of deference to custom, but from a belief into which they have fallen that they are true gods, and that those are not to be listened to who hold that the objects of their worship are not true gods.
Celsus, indeed, says that “they do not take them for gods, but only as offerings dedicated to the gods.” But he does not prove that they are not rather dedicated to men than, as he says, to the honour of the gods themselves; for it is clear that they are the offerings of men who were in error in their views of the Divine Being. Moreover, we do not imagine that these images are representations of God, for they cannot represent a being who is invisible and incorporeal. But as Celsus supposes that we fall into a contradiction, while on the one hand we say that God has not a human form, and on the other we profess to believe that God made man the image of Himself, and created man the image of God; our answer is the same as has been given already, that we hold the resemblance to God to be preserved in the reasonable soul, which is formed to virtue, although Celsus, who does not see the difference between “being the image of God,” and “being created after the image of God,” pretends that we said, “God made man His own image, and gave him a form like to His own.”
But this also has been examined before.
Source: Against Celsus (New Advent)