Diatesseron

The Diatessaron; (Syriac: ܐܘܢܓܠܝܘܢ ܕܡܚܠܛܐ‎, translit. Ewangeliyôn Damhalltê), (c. 160–175) is the most prominent early Gospel harmony, and was created by Tatian, an early Christian Assyrian apologist and ascetic. Tatian sought to combine all the textual material he found in the four gospels—Matthew, Mark, Luke, and John—into a single coherent narrative of Jesus's life and death. However, and in contradistinction to most later gospel harmonists, Tatian appears not to have been motivated by any aspiration to validate the four separate canonical gospel accounts; or to demonstrate that, as they stood, they could each be shown as being without inconsistency or error.

Tatian's harmony follows the gospels closely in terms of text but, in order to fit all the canonical material in, he created his own narrative sequence, which is different from both the synoptic sequence and John's sequence; and occasionally creates intervening time periods that are found in none of the source accounts. This sequence is coherent and consistent within itself, but not necessarily consistent with that in all or any of the separate canonical gospels; and Tatian apparently applies the same principle in respect of the narrative itself. Where the gospels differ from one another in respect of the details of an event or teaching; the Diatessaron resolves such apparent contradictions by selecting one or another alternative wording and adding consistent details from the other gospels; while omitting apparent duplicate matter, especially across the synoptics. Hence, in respect of the healing of the blind at Jericho the Diatessaron reports only one blind man, Bartimeaus, healed by Jesus when leaving the city according to the account in Mark 10:46ff (expanded with phrases from Luke 18:36-37); consequently omitting any separate mention of two unnamed blind men healed by Jesus leaving Jericho (Matthew 20:29ff), and also the healing by Jesus entering Jericho the previous day of a single unnamed blind man (Luke 18:35ff).

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