The Medieval Church · c. 1458–1461
The Fortress of Faith
Fortalitium Fidei
Alonso de Espina · d. c. 1464
What it is
A four-part attack on heretics, Jews, Muslims, and demons, urging the Spanish crown to establish an inquisition against converts suspected of relapsing.
Why it lasted
Catalogued because it must be known: it circulated the accusations that helped bring the Spanish Inquisition into being twenty years later.
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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