CCC 1159 The sacred image, the liturgical icon, principally represents Christ. It cannot represent the invisible and incomprehensible God, but the incarnation of the Son of God has ushered in a new “economy” of images:
Previously God, who has neither a body nor a face, absolutely could not be represented by an image. But now that he has made himself visible in the flesh and has lived with men, I can make an image of what I have seen of God. .. and contemplate the glory of the Lord, his face unveiled.1
1 St. John Damascene, De imag. 1, 16: PG 96: 1245-1248.