Catechism of the Catholic Church §909 — excerpt
"Moreover, by uniting their forces let the laity so remedy the institutions and conditions of the world when the latter are an inducement to sin, that these may be conformed to the norms of justice, favoring rather than hindering the practice of virtue.
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.
Also cites: LG 36 # 3