Catechism of the Catholic Church §2117 — excerpt
All practices of magic or sorcery, by which one attempts to tame occult powers, so as to place them at one's service and have a supernatural power over others - even if this were for the sake of restoring their health - are gravely contrary to the virtue of religion.
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.