37 Finally, the arts modeled on the supreme exemplar of all beauty which is God Himself, from whom is derived all the beauty to be found in nature, are more securely withdrawn from vulgar concepts and more efficaciously rise towards the ideal, which is the life of all art. And how fruitful of good has been the principle of employing them in the service of divine worship and of offering to the Lord everything that is deemed to be worthy of him, by reason of its richness, its goodness, its elegance of form. This principle has created sacred art, which became and still continues to be the foundation of all profane art. We have recently touched upon this in a special motu proprio, when speaking of the restoration of the Roman Chant according to the ancient tradition and of sacred music. And the same rules are applicable to the other arts, each in its own sphere, so that what has been said of the Chant may also be said of painting, sculpture, architecture; and towards all these most noble creations of genius the Church has been lavish of inspiration and encouragement. The whole human race, fed on this sublime ideal, raises magnificent temples, and here in the House of God, as in its own house, lifts up its heart to heavenly things in the midst of the treasures of all beautiful art, with the majesty of liturgical ceremony, and to the accompaniment of the sweetest of song.
Source: Iucunda Sane (Vatican.va)