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. 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. Though the Arabic translations that have survived suggest that Tatian was relying on a previous harmony, so little of his Diatessaron has survived, first the meticulous though not completely effective suppression it received in the 4th century, and then 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, 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 harmonization was replaced in the 5th century by the four gospels individually and gradually developed a reputation for being heretical. The name 'Diatessaron' is Greek for 'through four'; the Syriac name for this gospel harmony is 'Ewangeliyôn Damhalltê' ('Gospel of the Mixed').

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 link

• Early Christian Writings: (http://www.earlychristianwritings.com/diatessaron.html) Diatessaron e-text and commentaries.

References

• William L. Petersen, "Textual evidence of Tatian's dependence upon Justin's Apomnemonegmata, N.T.S. 36 (1990) 512-534.
• Empirical Models for Biblical Criticism. Ed. Jeffrey Tigay, Philadelphia: University of Pennsylvania Press, 1986