Catechism of the Catholic Church §1148 — excerpt
Inasmuch as they are creatures, these perceptible realities can become means of expressing the action of God who sanctifies men, and the action of men who offer worship to God.
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.