The Church Fathers · c. 598–615
On Ecclesiastical Offices
De Ecclesiasticis Officiis
Isidore of Seville · c. 560–636
What it is
An account of the origin of each order of ministry and each part of the liturgy, written to explain to Spanish clergy why they do what they do.
Why it lasted
The earliest systematic explanation of the Western liturgy, and a principal source for the Mozarabic rite before it was suppressed.
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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