Epistle of Barnabas,
somewhere between c.70-135 AD (jan 1, 70 – jan 1, 135)
Description:
This epistle appears to have been written after the destruction of Jerusalem in 70 AD, but also before it was rebuilt by Hadrian following the revolt in 132-135 AD. Outside of that, it's not very easy to be more accurate with a date as the author is anonymous.
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Date: