Catechism of the Catholic Church §1158 — excerpt
The harmony of signs (song, music, words, and actions) is all the more expressive and fruitful when expressed in the cultural richness of the People of God who celebrate.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: SC 119 · SC 118 · 121