A nice overview of Abgar V and his apocryphal correspondence with Jesus. Eusebius preserves the letters in a Greek translation, but they also survive in the original Syriac, notably in the Doctrine of Addai.
For PaleoJudaica posts on the Agbarid dynasty and the Abgar letters, as well as on ancient Edessa, start here and follow the links. Cross-file under Syriac Watch.
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