See diatessaron (interval) for the musical term.

Tatian's Diatessaron was one of a number of harmonies of the four Gospels, that is, the material of the four distinct Gospels rewritten as a continuous narrative resolving all conflicting statements. It contained most of the gospels' material except, according to Theodoret, for the two irreconcilable genealogies of Jesus. This work was produced ca. 175 AD by Tatian, a Syrian Christian who was a pupil of Justin Martyr in Rome. It is generally agreed that Justin already possessed some sort of a harmony text. No version of Diatessaron in Syriac or Greek has survived. Though the Arabic translations that have survived suggest that Tatian was relying on a previous harmony, so little of his Diatessaron has survived, first by the meticulous though not completely effective suppression it received in the 4th century, and then by the piecemeal accretions, adjustments and corrections its text received, that many questions remain to what extent it was a new work.

There is even disagreement about what language Tatian used for its original composition, whether Syriac or Greek. However, modern scholarship tends to favour a Syriac origin. The Diatessaron was used in the Syrian Church for centuries and was quoted or alluded to by Syrian writers: Ephraem wrote a lost commentary on it [1], but Theodoret, bishop of Cyrrhus on the Euphrates in upper Syria in 423, sought out and found more than two hundred copies of the Diatessaron, which he "collected and put away, and introduced instead of them the Gospels of the four evangelists". Thus the harmonisation was replaced in the 5th century by the canonical four gospels individually and gradually developed a reputation for having been heretical. The name 'Diatessaron' is Greek for 'through four'; the Syriac name for this gospel harmony is 'Ewangeliyôn Damhalltê' ('Gospel of the Mixed'). The Syrian Church also rejected John's Revelation and the Pastoral epistles . They were included again only in the middle of the sixth century.

In the tradition of Gospel harmonies, there is another Diatessaron, reportedly written by one Ammonius Saccas, to correct perceived deficencies in Tatian's. (Note that this Ammonius Saccas is probably not the Ammonius Saccas who taught Origen and Plotinus, but rather a different philosopher with the same name.) None of this revised Diatessaron survives.

External links

• Early Christian Writings: Diatessaron e-text and commentaries.
• Ante-Nicene Fathers vol. X: based on an 11th century Arabic translation from the Syriac

References

• William L. Petersen, "Textual evidence of Tatian's dependence upon Justin's Apomnemonegmata, New Testament Studies 36 (1990) 512-534.
• Jeffrey Tigay, editor. Empirical Models for Biblical Criticism. Philadelphia: University of Pennsylvania Press, 1986