The Church Fathers · c. 170; survives in fragments
The Catholic Letters
Dionysius of Corinth
What it is
Seven letters to churches across the Mediterranean, quoted by Eusebius. One thanks Rome for the money it has sent to poorer congregations since Clement's day; another complains that his own letters are already being tampered with by people who add and subtract at will.
Why it lasted
The earliest evidence of a bishop writing to churches he has no jurisdiction over as a matter of course, and the earliest complaint about the corruption of Christian texts in transmission.
Scripture it works from
Where to read it
Public domain and free to read in full, though not held here. The archives below have it.
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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