The Medieval Church · c. 1063–1070
On the Body and Blood of the Lord
Lanfranc of Bec · c. 1005–1089
What it is
The reply to Berengar, arguing that the substance of the bread is converted while its appearances remain, and using the very dialectic Berengar had deployed.
Why it lasted
It supplied the vocabulary that hardened into transubstantiation at the Fourth Lateran Council a century and a half 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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