EH 4.29.6 mentions the Diatessaron : "But their original founder, Tatian, formed a certain combination and collection of the gospels, I know not how, to which he gave the title Diatessaron, and which is still in the hands of some. Source: Internet
In a lost writing entitled On Perfection according to the Doctrine of the Savior, Tatian designates matrimony as a symbol of the tying of the flesh to the perishable world and ascribed the "invention" of matrimony to the devil. Source: Internet
Other lost writings of Tatian include a work written before the Oratio ad Graecos that contrasts the nature of man with the nature of the animals, and a Problematon biblion, which aimed to present a compilation of obscure Scripture sayings. Source: Internet
The early development of the Syrian church furnishes a commentary on the attitude of Tatian in practical life. Source: Internet
"In 170 Tatian sought to find a solution by composing a single narrative out of Matthew, Mark, and Luke, with some additional oral material." Source: Internet
Tatian added no significant wording to the textual material he took from the separate gospels. Source: Internet