is also
called Aphthonius, constructed a Gospel after the likeness of the
_Diatessaron_ of Ammonius, mentioned by Eusebius in his prologue to
the Canons which he made for the Gospel. Elias sought for that
Diatessaron and could not find it, and in consequence constructed
this after its likeness. And the said Elias finds fault with
several things in the Canons of Eusebius, and points out errors in
them, and rightly. But this copy (work) which Elias composed is not
often met with.

This statement is explicit and careful. The writer distinguishes two
older works, bearing the name of _Diatessaron_, composed respectively by
Tatian and Ammonius. In addition he mentions a third, composed at a
later date by this Elias. Of the work of Ammonius of Alexandria (about
A.D. 220) Eusebius, as Bar-Salibi correctly states, gives an account in
his _Letter to Carpianus_, prefixed to his Canons. It was quite
different in its character from the _Diatessaron_ of Tatian. The
_Diatessaron_ of Tatian was a patchwork of the Four Gospels, commencing
with the preface of St John. The work of Ammonius took the Gospel of St
Matthew as its standard, preserving its continuity, and placed side by
side with it the parallel passages from the other Gospels [281:1]. The
principle of the one work was _amalgamation_; of the other,
_comparison_. No one who had seen the two works could confuse them,
though they bore the same name, _Diatessaron_. Eusebius keeps them quite
distinct. So does Bar-Salibi. Later on in his commentary, we are told,
he quotes both works in the same place [281:2]. When therefore he
relates that Ephraem wrote a commentary on the _Diatessaron_ of Tatian,
he is worthy of all credit. From the last witness we have learnt that
the _Diatessaron_ was commonly read in the churches of Edessa; and it
was therefore most natural that this famous Edessan father should choose
it for commenting upon.

It is quite true that other Syrian writers have confused these two
_Diatessarons_ [281:3]. But this fact is only valid to show that
confusion was possible; it is powerless to impugn the testimony of this
particular author, who shows himself in this passage altogether
trustworthy. Who would think of throwing discredit on Lord Macaulay or
Mr Freeman, because Robertson or Hume may be inaccurate?

4. Our next witness is more important than any. The famous Greek father
Theodoret became bishop of Cyrus or Cyrrhus, near t