The Church offers us five points on the theology of sacred images, so let’s consider them in turn:
240. According to the teaching of the Church, sacred images are:
• iconographical transcriptions of the Gospel message, in which image and revealed word are mutually clarified; ecclesiastical tradition requires that images conform “to the letter of the Gospel message” (Council of Nicea II, Definitio de sacris imaginibus, in Conciliorum Oecumeniorum Decreta, cit., p. 135 (not contained in DS));
Images preach the Gospel: do our artists express this? I suspect the DPPL is talking about something other than a mandate that images accurately depict Gospel scenes. I think we’re talking about the essence of the Lord’s teaching: seeking, finding, discipleship, joy, charity–the whole thing
• sacred signs which, in common with all liturgical signs, ultimately refer to Christ; images of the Saints “signify Christ who is glorified in them”(Catechism 1161);
This is a principle of iconography–notice that the Blessed Mother always gestures to Christ. Any image should be saying to us: “There is Christ. Go to him.” The image is to be a window, not a show for its own sake.
• memorials of our (sisters and brothers) who are Saints, and who “continue to participate in the salvation of the world, and to whom we are united, above all in sacramental celebrations”(Catechism 1161);
Basic Communion of Saints: the Church is peopled by not only the living, but also those who now live in eternal glory.
• an assistance in prayer: contemplation of the sacred images facilitates supplication and prompts us to give glory to God for the marvels done by his grace working in the Saints; – a stimulus to their imitation because “the more the eye rests on these sacred images, the more the recollection of those whom they depict grows vivid in the contemplative beholder” (Council of Nicea II, Definitio de sacris imaginibus, in DS 601); the faithful tend to imprint on their hearts what they contemplate with the eye: “a true image of the new man (or person)”, transformed in Christ, through the power of the Holy Spirit, and in fidelity to his proper vocation;
Images help many of us pray. Think of the various types of prayer: intercessory, contrition, adoration, and so on. For different people, different ways are working better than some others. Living as we do in a visual-oriented culture, this is probably as true as ever.
• and a form of catechesis, because “through the history of the mysteries of our redemption, expressed in pictures and other media, the faithful are instructed and confirmed in the faith, since they are afforded the means of meditating constantly on the articles of faith” (Council of Trent, Decretum de sacris invocatione, veneratione et reliquiis Sanctorum, et sacris imaginibus, in DS 1824).
Images also teach. This would have been vital in the centuries prior to the advent of the printed word. But it’s still important today, and not just for the young who have yet to learn to read. Good art communicates on significantly deeper levels, and that is a profound responsibility for any artist.
The Directory on Popular Piety and the Liturgy is online at the Vatican site.