The Church Fathers · c. 605–615
The Book of the Union
Babai the Great · c. 551–628
What it is
A systematic christology of two natures and two hypostases in one person of union, worked out for a church living under Persian rule with no emperor to appeal to.
Why it lasted
The definitive doctrinal statement of the Church of the East, still its official christology fourteen centuries 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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