Catechism of the Catholic Church §2118 — excerpt
God's first commandment condemns the main sins of irreligion: tempting God, in words or deeds, sacrilege, and simony.
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.