Tatian's Gospel not been different in various respects from our four Gospels, such summary treatment would have been totally {154} unwarrantable. The statement, moreover, that in place of Tatian's Gospel, Theodoret "introduced the Gospels of the four Evangelists," seems to indicate that the displaced Gospel was not a compilation from them, but a substantially different work. Had this not been the case, Theodoret would naturally have qualified such an expression. Speaking of the difficulty of distinguishing Tatian's Harmony from others which must, the writer supposes, have been composed in his time, Dr. Donaldson points out: "And then we must remember that the Harmony of Tatian was confounded with the Gospel according to the Hebrews; and it is not beyond the reach of possibility that Theodoret should have made some such mistake."(1) That is to say, that the only writer who refers to Tatian's Gospel who professes to have seen the work is not only "not to be depended on," but may actually have mistaken for it the Gospel according to the Hebrews. There is, therefore, no authority for saying that Tatian's Gospel was a harmony of four Gospels at all, and the name Diatessaron was not only not given by Tatian himself to the work, but was probably the usual foregone conclusion of the Christians of the third and fourth centuries, that everything in the shape of evangelical literature must be dependent on the Gospels adopted by the Church. Those, however, who called the Gospel used by Tatian the Gospel according to the Hebrews must apparently have read the work, and all that we know confirms their conclusion. The Gospel was, in point of fact, found in wide circulation precisely in the places in which, earlier, the Gospel according to the Hebrews was more particularly current.(2) The singular {155} fact that the earliest reference to Tatian's "Harmony," is made a century and a half after its supposed composition, and that no writer before the fifth century had seen the work itself, indeed that only two writers before that period mention it at all, receives its natural explanation in the conclusion that Tatian did not compose any Harmony at all, but simply made use of the same Gospel as his master Justin Martyr, namely, the Gospel according to the Hebrews,(1) by which name his Gospel had been actually called by those best informed.