Christianity contains nothing untried and abnormal. The very use of sacred images belongs to an ancient tradition, as worthy examples of faith have testified. The first example is that of the image of our Lord Jesus Christ, sent to King Abgar; this image on a wooden tablet showed the outlines of His bodily form, similar to images painted with colors. The second example is that of the image not painted by human hands (acheropita) of her who gave birth without seed: it is found at Lidda, a city also called Diospolis. The image is painted in very bright colors and shows the body of the Mother of God, three cubits in height. It was venerated in the time of the apostles on the western wall of the temple that they built. It is so finely done that it appears to have been produced by the hand of a painter. It clearly shows her purple habit, her hands, her face, and all of her outward form, as can still be affirmed today. They say that Julian, that apostate and enemy of Christ, heard about the painting, he wanted to know more about it. So he sent some Jewish painters [to examine it], who informed him that it was genuine; Julian, dumbfounded, had no desire to investigate further.
It is told that the temple was constructed when the Mother of God was still living. Going up to Zion, where she lived, the apostles said to her, “Where were you, Lady? We have built you a house at Lidda.” Mary answered them, “I was with you, and I am still with you.” Returning to Lidda and entering the temple, they found her complete image there, as she had told them. This is what an ancient local tradition has testified from the beginning, and the tradition lives today.
Third example. Everyone witnesses to the fact that Luke, apostle and evangelist, painted the incarnate Christ and His immaculate Mother with his own hands and that these images are conserved in Rome with fitting honor. Others assert these these images are kept at Jerusalem. Even the Jew Josephus tells us that the Lord looked just like the picture: eyebrows meeting in the middle, beautiful eyes, long face, somewhat oval, of a fair height. This was undoubtedly His appearance when He dwelt among men. Josephus describes the appearance of the Mother of God in the same way, as it appears today in the image that some call the “Roman woman”. (On the Veneration of Sacred Images PG 97, 1301-4)