Catechism of the Catholic Church §1151 — excerpt
Signs taken up by Christ. In his preaching the Lord Jesus often makes use of the signs of creation to make known the mysteries of the Kingdom of 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.