Catechism of the Catholic Church §1760 — excerpt
A morally good act requires the goodness of its object, of its end, and of its circumstances together.
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.