Tatian was a teacher of rhetoric, an Assyrian by birth, who was converted to Christianity by Justin Martyr, but after his death fell into heresy, leaning towards the Valentinian Gnosticism, and combining with this an extreme asceticism.

The death of Justin is clearly the pivot on which his date will hinge. If we are to accept the conclusions of Mr. Hort this will have occurred in the year 148 A.D.; according to Volkmar it would fall not before 155 A.D., and in the ordinary view as late as 163- 165 A.D. [Endnote 238:1] The beginning of Tatian's literary activity will follow accordingly.

Tatian's first work of importance, an 'Address to Greeks,' which is still extant, was written soon after the death of Justin. It contains no references to the Synoptic Gospels upon which stress can be laid.

An allusion to Matth. vi. 19 in the Stromateis of Clement [Endnote 238:2] has been attributed to Tatian, but I hardly know for what reason. It is introduced simply by [Greek: tis (biazetai tis legon)], but there were other Encratites besides Tatian, and the very fact that he has been mentioned by name twice before in the chapter makes it the less likely that he should be introduced so vaguely.

The chief interest however in regard to Tatian centres in his so- called 'Diatessaron,' which is usually supposed to have been a harmony of the four Gospels.

Eusebius mentions this in the following terms: 'Tatian however, their former leader, put together, I know not how, a sort of patchwork or combination of the Gospels and called it the "Diatessaron," which is still current with some.' [Endnote 239:1]

I am rather surprised to see that Credner, who is followed by the author of 'Supernatural Religion,' argues from this that Eusebius had not seen the work in question [Endnote 239:2]. This inference is not by any means conveyed by the Greek. [Greek: Ouk oid' hopos] (thus introduced) is an idiomatic phrase referring to the principle on which the harmony was constructed, and might well be paraphrased 'a curious sort of patchwork or dovetailing,' 'a not very intelligible dovetailing,' &c. Standing in the position it does, the phrase can hardly mean anything else. Besides it is not likely that Eusebius, an eager collector and reader of books, with the run of Pamphilus' library, should not have been acquainted with a work that he says himself was current in more quarters than one. Eusebius, it will be observed, is quite explicit in his statement. He says that the Diatessaron was a harmony of the Gospels, i.e. (in his sense) of our present Gospels, and that Tatian gave the name of Diatessaron to his work himself. We do not know upon what these statements rest, but there ought to be some valid reason before we dismiss them entirely.

Epiphanius writes that 'Tatian is said to have composed the Diatessaron Gospel which some call the "Gospel according to the Hebrews"' [Endnote 240:1]. And Theodoret tells us that 'Tatian also composed the Gospel which is called the Diatessaron, cutting out the genealogies and all that shows the Lord to have been born of the seed of David according to the flesh.' 'This,' he adds, 'was used not only by his own party, but also by those who followed the teaching of the Apostles, as they had not perceived the mischievous design of the composition, but in their simplicity made use of the book on account of its conciseness.' Theodoret found more than two hundred copies in the churches of his diocese (Cyrrhus in Syria), which he removed and replaced with the works of the four Evangelists [Endnote 240:2].

Victor of Capua in the sixth century speaks of Tatian's work as a 'Diapente' rather than a 'Diatessaron' [Endnote 240:3]. If we are to believe the Syrian writer Bar-Salibi in the twelfth century, Ephrem Syrus commented on Tatian's Diatessaron, and it began with the opening words of St. John. This statement however is referred by Gregory Bar-Hebraeus not to the Harmony of Tatian, but to one by Ammonius made in the third century [Endnote 241:1].

Here there is clearly a good deal of confusion.

But now we come to the question, was Tatian's work really a Harmony of our four Gospels? The strongest presumption that it was is derived from Irenaeus. Irenaeus, it is well known, speaks of the four Gospels with absolute decision, as if it were a law of nature that their number must be four, neither more nor less [Endnote 241:2], and his four Gospels were certainly the same as our own. But Tatian wrote within a comparatively short interval of Irenaeus. It is sufficiently clear that Irenaeus held his opinion at the very time that Tatian wrote, though it was not published until later. Here then we have a coincidence which makes it difficult to think that Tatian's four Gospels were different from ours.