Here is an interesting quote from Eusebius (courtesy of www.peshito.com):
Eusebius says, (H. E. iv. 22) that:
"Hegesippus, (who lived and wrote about A. D. 188,) made some quotations from the Gospel according to the Hebrews, and from the Syriac Gospel"
Now this claims that in the days of Hegesippus, a Syriac Gospel existed, and that it was a different book from the Gospel according to the Hebrews.
And in the Passio Sancti Procopii Martyris, (annexed by Valesius to the Hist. Eccles. of Eusebius, lib. viii. c. 1, ed. Amsterdam, 1695. Annotatt, p. 154,) the martyr is said to have been born at Jerusalem, and to have passed his life at Scythopolis, where he performed three functions in the church,- " unum in legendi officio, alterum in Syri interpretatione sermonis, et tertium adversus daemones manus impositione consummans ;" until his martyrdom, under Diocletian, A. D. 303.
The words "Syri interpretatione sermonis", explicitly, make him the public translator, (of the Scriptures, undoubtedly,) from the Syriac language into some other, the Greek, most probably: for we may suppose there were some Greeks in the Syrian church of Scythopolis, for whose benefit the Scripture lessons were translated as they were read.