On Images: A capsule of the argument by John of Damascus in On the Orthodox Faith:
But since some find fault with us for worshiping and honoring the image of our Saviour and that of Our Lady, and those, too, of the rest of the saints and servants of Christ, let them remember that in the beginning God created man after His own image. On what grounds, then, do we show reverence to one another unless it is because we are made after God's image? For as Basil, that much-versed expounder of divine things, says, the honor given to the images passes over to the prototype. Now a prototype is that which is imaged, from which the derivative is obtained. Why was it that the Mosaic people honored on all hands the tabernacle which bore an image and type of heavenly things, or rather of the whole creation? God indeed said to Moses, "See that you make them after the pattern for them, which is being shown you on the mountain" (Ex 25:40) The cherubim, too, which overshadow the mercy seat, are they not the work of men's hands? What, further, is the celebrated Temple at Jerusalem? Is it not handmade and fashioned by the skill of men?
Moreover the divine Scripture blames those who worship graven images, but also those who sacrifice to demons. The Greeks sacrificed and the Jews also sacrificed: but the Greeks was rejected and condemned, but the sacrifice of the just was every acceptable to God. For Noah sacrificed, and God smelled a sweet savor, receiving the fragrance of the right choice and goodwill towards Him. And so the graven images of the Greeks, since they were images of deities, were rejected and forbidden.
But besides this, who can make an imitation of the invisible, incorporeal, uncircumscribed, formless God? Therefore to give form to the Deity is that height of folly and impiety. And hence it is that in the Old Testament the use of images was not common. But after God in the depths of His bowels of pity became in truth man for our salvation, not as He was seen by Abraham in the semblance of a man, nor as He was seen by the prophets, but in being truly man, and after He lived upon the earth and dwelt among men, worked miracles, suffered, was crucified, rose again, and was taken back to heaven, since all these things actually took place and were seen by men, they were written for the remembrance and though we saw not, we may still, hearing and believing, obtain the blessing of the Lord. But seeing that not every one has a knowledge of letters nor time for reading, the Fathers gave their sanction to depicting these events on images as being acts of great heroism, in doubtless, when we have not the image of Christ's crucifixion, His saving passion is brought back to remembrance, and we fall down and worship not the material but that which is imaged: just as we do not worship the material of which the Gospels are made, nor the material of the icons, but that which these typify.
For wherein does the cross, which typifies the Lord, differ from a cross that does not do so? It is just the same also in the case of the Mother of the Lord. For the honor which we give to her is referred to Him who was made of her incarnate. And similarly also the brave acts of holy men stir us up to be brave and to emulate and imitate their valor and to glorify God. For as we said, the honor that is given to the best of fellow servants is a proof of goodwill towards our common Lady, and the honor rendered to the image passes over to the prototype.
John of Damascus: On the Orthodox Faith
PS: sometimes it is constructive to go to 'First Sources' and simply let them speak for themselves.
