Catechism of the Catholic Church §320 — excerpt
God created the universe and keeps it in existence by his Word, the Son "upholding the universe by his word of power" (Heb 1:3), and by his Creator Spirit, the giver of life.
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.