The Church Fathers · c. 320; survives in fragments
Thalia
Arius · c. 256–336
What it is
A popular verse exposition, apparently written to be sung, arguing that the Son is the first and greatest of creatures, made before time but not eternal.
Why it lasted
The most consequential heresy in Christian history in its author's own words — preserved only in the quotations of Athanasius, who was refuting it.
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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