Catholic Encyclopedia

An online encyclopedia that indexes much knowledge from the Roman Catholic Church. The sheer volume of work here is impressive and most of the information is useful to multiple Christian denominations (for example, this article on Bethlehem), but the site is an excellent resource for all things Roman Catholic.

In addition to the Encyclopedia, the organization New Advent also hosts a site on early Church Fathers and the Summa Theologica of Thomas Aquinas.

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