Catechism of the Catholic Church §345 — excerpt
The sabbath - the end of the work of the six days. the sacred text says that "on the seventh day God finished his work which he had done", that the "heavens and the earth were finished", and that God "rested" on this day and sanctified and blessed it.
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.