2129 The divine injunction included the prohibition of every representation of God by the hand of man. Deuteronomy explains: “Since you saw no form on the day that the Lord spoke to you at Horeb out of the midst of the fire, beware lest you act corruptly by making a graven image for yourselves, in the form of any figure....” (Deut. 4:15–16) It is the absolutely transcendent God who revealed himself to Israel. “He is the all,” but at the same time “he is greater than all his works.” (Sir. 43:27–28) He is “the author of beauty.” (Wis. 13:3)
2130 Nevertheless, already in the Old Testament, God ordained or permitted the making of images that pointed symbolically toward salvation by the incarnate Word: so it was with the bronze serpent, the ark of the covenant, and the cherubim. (cf. Num. 21:4–9; Wis. 16:5–14; Jn. 3:14–15; Ex. 25:10–22; 1 Kings 6:23–28, 7:23–26)
2131 Basing itself on the mystery of the incarnate Word, the seventh ecumenical council at Nicaea (787) justified against the iconoclasts the veneration of icons — of Christ, but also of the Mother of God, the angels, and all the saints. By becoming incarnate, the Son of God introduced a new “economy” of images.
2132 The Christian veneration of images is not contrary to the first commandment which proscribes idols. Indeed, “the honor rendered to an image passes to its prototype,” and “whoever venerates an image venerates the person portrayed in it.” ( St. Basil, De Spiritu Sancto 18, 45: PG 32, 149C; Council of Nicaea II: DS 601; cf. Council of Trent: DS 1821-1825; Vatican Council II: SC 126; LG 67.) The honor paid to sacred images is a “respectful veneration,” not the adoration due to God alone:
Religious worship is not directed to images in themselves, considered as mere things, but under their distinctive aspect as images leading us on to God incarnate. the movement toward the image does not terminate in it as image, but tends toward that whose image it is. (St. Thomas Aquinas, Summa Theologica II-II, 81, 3 ad 3).
Christ our Lord, who has bestowed upon us the light of the knowledge of himself, and has redeemed us from the darkness of idolatrous madness, having espoused to himself the Holy Catholic Church without spot or defect, promised that he would so preserve her (...) But some, not considering of this gift, and having become fickle through the temptation of the wily enemy, have fallen from the right faith; for, withdrawing from the traditions of the Catholic Church, they have erred from the truth (...) because certain priests, priests in name only, not in fact, had dared to speak against the God-approved ornament of the sacred monuments.
And, forsooth, following profane men, led astray by their carnal sense, they have calumniated the Church of Christ our God, which he has espoused to himself, and have failed to distinguish between holy and profane, styling the images of our Lord and of his Saints by the same name as the statues of diabolical idols. (...)
To make our confession short, we keep unchanged all the ecclesiastical traditions handed down to us, whether in writing or verbally, one of which is the making of pictorial representations, agreeable to the history of the preaching of the Gospel, a tradition useful in many respects, but especially in this, that so the incarnation of the Word of God is shown forth as real and not merely phantastic, for these have mutual indications and without doubt have also mutual significations.
Moreover, I am well pleased that there should be images in the churches of the faithful, especially the image of our Lord Jesus Christ and of the holy Mother of God, of every kind of material, both gold and silver and of every colour, so that his incarnation may be set forth to all men. Likewise there may be painted the lives of the Saints and Prophets and Martyrs, so that their struggles and agonies may be set forth in brief, for the stirring up and teaching of the people, especially of the unlearned.
For if the people go forth with lights and incense to meet the laurata and images of the Emperors when they are sent to cities or rural districts, they honour surely not the tablet covered over with wax, but the Emperor himself. How much more is it necessary that in the churches of Christ our God, the image of God our Saviour and of his spotless Mother and of all the holy and blessed fathers and ascetics should be painted?