If you go down to the very bottom of our pages, you will notice this text: “Except where otherwise noted, content on this site is licensed under the Creative Commons Attribution – Share Alike License.”
This means that the text on Catholicism.org is now free for the using, as long as the conditions of that license are met.
You can even make “derivative works,” a permission which will allow our articles to be inserted wholesale into something like Wikepedia, as long as the site it’s being posted on publishes the derivative work under the same or a similar agreement — as Wikipedia does. (A “derivative work” would be an edited, shortened, or expanded version of our original text.) So, if you are a Wikipedia editor, have at it; everything is in place on Wikipedia already to make this all legal and ethical.
The easiest way to make sure you are reproducing our work properly is to post the Creative Commons Attribution – Share Alike License on your own site — even if it’s only for that one page — and make a linkback to our original.