The story of how King Abgar and Jesus had corresponded was first recounted in the 4th century by the church historian Eusebius of Caesarea in his Ecclesiastical History (i.13 and iii.1) and it was retold in elaborated form by Ephrem the Syrian.
Helmut Koester regards the development of tradition of Thaddaeus' activity in Edessa as part of an effort to build the authority of the orthodox or Palutian2 faction in Syria against the Manicheans and gnostics, who had an older and stronger presence in the area and traced their lineage to Thomas the Apostle.34 He considers the Palutian faction to have come to Edessa around 200 CE and only become significant in the fourth century.5
Noegel, Scott B.; Wheeler, Brannon M. (2010-04-01). The A to Z of Prophets in Islam and Judaism. Scarecrow Press. p. 89. ISBN 9781461718956. 9781461718956 ↩
The group now understood as the orthodox faction was known as the Palutians in Syria at this time. (Koester 1965, p. 305) - Koester, Helmut (July 1965). "ΓΝΩΜΑΙ ΔΙΑΦΟΡΟΙ: The Origin and Nature of Diversification in the History of Early Christianity". Harvard Theological Review. 58 (3): 279–318. doi:10.1017/S0017816000031400. JSTOR 1508818. S2CID 163149876. https://doi.org/10.1017%2FS0017816000031400 ↩
Koester 1965, p. 296,305. - Koester, Helmut (July 1965). "ΓΝΩΜΑΙ ΔΙΑΦΟΡΟΙ: The Origin and Nature of Diversification in the History of Early Christianity". Harvard Theological Review. 58 (3): 279–318. doi:10.1017/S0017816000031400. JSTOR 1508818. S2CID 163149876. https://doi.org/10.1017%2FS0017816000031400 ↩
Cf. Bauer, Walter (1909). Das Leben Jesu im Zeitalter der neutestamentlichen Apokryphen (in German). Tübingen, Germany: J. C. B. Mohr. pp. 444–445. /wiki/Walter_Bauer ↩
Koester 1965, p. 305-306. - Koester, Helmut (July 1965). "ΓΝΩΜΑΙ ΔΙΑΦΟΡΟΙ: The Origin and Nature of Diversification in the History of Early Christianity". Harvard Theological Review. 58 (3): 279–318. doi:10.1017/S0017816000031400. JSTOR 1508818. S2CID 163149876. https://doi.org/10.1017%2FS0017816000031400 ↩
Saint-Laurent et al. 2015. - Saint-Laurent, Jeanne-Nicole Mellon; Michelson, David A.; Zanetti, Ugo; Detienne, Claude, eds. (5 November 2015). "Addai (Teaching of) (text)". Bibliotheca Hagiographica Syriaca. Retrieved 31 August 2017. http://syriaca.org/work/921 ↩
Walker, Alexander (1885). "Translator's introductory notice to the apocryphal acts of the apostles" . In Roberts, Alexander; Donaldson, James (eds.). Ante-Nicene Christian Library. Edinburgh: T. & T. Clark.. Note: Walker conflates the 'Acts of Thaddeus with the Doctrine of Addai. /wiki/File:Wikisource-logo.svg ↩
French national library http://catalogue.bnf.fr/ark:/12148/cb366840314 ↩