The Apostolic Age · c. 124–125; one fragment survives
Apology to Hadrian
Quadratus
What it is
The first Christian defence addressed to an emperor, of which Eusebius preserves a single paragraph noting that some healed by Jesus had lived into the writer's own lifetime.
Why it lasted
The earliest Christian apology known by name, and the opening of a genre that ran for three centuries.
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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