The Church Fathers · 434
The Commonitory
Vincent of Lérins · d. c. 445
What it is
How to tell catholic truth from novelty: hold what has been believed everywhere, always, and by everyone — with a careful account of how doctrine may nevertheless grow.
Why it lasted
The Vincentian canon, quoted in every subsequent argument about development of doctrine, by Newman above all.
Where to read it
This work is in the public domain and can be read in full, free, at the archives below. The Library catalogues it; it does not host the text.
These open a search on each archive rather than a direct link, which is the honest way to point at an edition nobody here has checked line by line.
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