The Diatessaron
Eusebius, HE. IV.29.6):
Tatian composed in some way a combination and collection of the gospels, and gave this the name of The Diatessaron (to\ dia\ tessa/rwn) and this is still extant in some places.
Theodoret of Cyrrhus (d.457/8), PG 83, "Haereticarum fabularum compendium ad Sporacium," 1.20 (= pp. 370-71); more familiarly known by the title, "Treatise on Heresies", writes:
He [Tatian] composed the Gospel which is called Diatessaron, cutting out the genealogies and such other passages as show the Lord to have been born of the seed of David after the flesh. This work was in use not only among persons belonging to his sect, but also among those who follow the apostolic doctrine, as they did not perceive the mischief of the composition, but used the book in all simplicity on account of its brevity. And I myself found more than two hundred such copies held in respect in the churches in our parts. All these I collected and put away, and I replaced them by the Gospels of the four Evangelists.
(No English translation of this work exists: the quotation is taken from J. M. Fuller’s article “Tatian” in W. Smith and H. Wace, A Dictionary of Christian Biography (4 vols.; London: John Murray, 1887) 4.795, via Leslie McFall, "Tatian's Diatessaron: Mischievous or Misleading?" Westminster Theological Journal 56.1 (Fall 1994): 87-114)
Online texts
Ante-Nicene Fathers vol. 10 Translated from Arabic version with preface.
Bibliography
See also Ephrem for his commentary on the Diatessaron.
