Theophilus of Antioch.

One of the Christian apologists.

Attributed text(s).
Against Marcion.
To Autolycus.
Against the Heresy of Hermogenes.
On the Gospel.
On the Proverbs of Solomon.

Available text(s).
Skeptik (Greek only).
CCEL: To Autolycus, books 1, 2, and 3 (English only).
Early Christian Writings: To Autolycus, books 1, 2, and 3 (English only).

Related text(s).

Useful links.
Theophilus at EarlyChurch.
Theophilus in the Catholic Encyclopedia.
Theophilus at Early Christian Writings.

Theophilus was a Christian apologist and bishop of Antioch who flourished late in century II.

Eusebius, History of the Church 4.20[.1]:

Και επι της Αντιοχεων δε εκκλησιας Θεοφιλος εκτος απο των αποστολων εγνωριζετο. τεταρτου μεν των εκεισε μετα Ηρωνα κατασταντος Κορνηλιου, μετα δε αυτον πεμπτω βαθμω την επισκοπην Ερωτος διαδεξαμενου.

At that time also in the church of Antioch, Theophilus was well known as the sixth from the apostles. For Cornelius, who succeeded Hero, was the fourth, and after him Eros, the fifth in order, had held the office of bishop.

Eusebius, History of the Church 4.24.1-3:

Του δε Θεοφιλου, ον της Αντιοχεων εκκλησιας επισκοπον δεδηλωκαμεν, τρια τα προς Αυτολυκον στοιχειωδη φερεται συγγραμματα, και αλλο προς την αιρεσιν Ερμογενους την επιγραφην εχον, εν ω εκ της αποκαλυψεως Ιωαννου κεχρηται μαρτυριαις. και ετερα δε τινα κατηχητικα αυτου φερεται βιβλια.

Of Theophilus, whom we have mentioned as bishop of the church of Antioch, three elementary works addressed to Autolycus are extant; also there is another writing entitled Against the Heresy of Hermogenes, in which he makes use of testimonies from the apocalypse of John, and finally certain other catechetical books.

Των γε μην αιρετικων ου χειρον και τοτε ζιζανιων δικην λυμαινομενων τον ειλικρινη της αποστολικης διδασκαλιας σπορον, οι πανταχοσε των εκκλησιων ποιμενες, ωσπερ τινας θηρας αγριους των Χριστου προβατων αποσοβουντες, αυτους ανειργον τοτε μεν ταις προς τους αδελφους νουθεσιαις και παραινεσεσιν, τοτε δε προς αυτους γυμνοτερον αποδυομενοι, αγραφοις τε εις προσωπον ζητησεσι και ανατροπαις, ηδη δε και δι εγγραφων υπομνηματων τας δοξας αυτων ακριβεστατοις ελεγχοις διευθυνοντες.

And as the heretics, no less then than at other times, were like tares, destroying the pure harvest of apostolic teaching, the pastors of the churches everywhere hastened to restrain them as wild beasts from the fold of Christ, at one time by admonitions and exhortations to the brethren, at another time by contending more openly against them in oral discussions and refutations, and again by correcting their opinions with most accurate proofs in written works.

Ο γε τοι Θεοφιλος συν τοις αλλοις κατα τουτων στρατευσαμενος δηλος εστιν απο τινος ουκ αγεννως αυτω κατα Μαρκιωνος πεπονημενου λογου, ος και αυτος μεθ ων αλλων ειρηκαμεν εις ετι νυν διασεσωσται. τουτον μεν ουν εβδομος απο των αποστολων της Αντιοχεων εκκλησιας διαδεχεται Μαξιμινος.

And that Theophilus also contended with the others against them is manifest from a certain discourse of no common merit written by him against Marcion. This work too, with the others of which we have spoken, has been preserved to the present day. Maximinus, the seventh from the apostles, succeeded him as bishop of the church of Antioch.

Jerome, On Famous Men 25:

Theophilus sextus Antiochensis ecclesiae episcopus, sub imperatore M. Antonino Vero librum contra Marcionem composuit, qui usque hodie exstat. feruntur eius et ad Autolycum tria volumina, et contra haeresim Hermogenis liber unus, et alii breves elegantesque tractatus ad aedificationem ecclesiae pertinentes. legi sub nomine eius in evangelium et in proverbia Salomonis commentarios, qui mihi cum superiorum voluminum elegantia et phrasi non videntur congruere.

Theophilus, sixth bishop of the church of Antioch, in the reign of the emperor Marcus Antoninus Verus composed a book Against Marcion, which is still extant, also three volumes To Autolycus and one Against the Heresy of Hermogenes and other short and elegant treatises, well fitted for the edification of the church. I have read, under his name, commentaries on the gospel and on the proverbs of Solomon which do not appear to me to correspond in style and language with the elegance and expressiveness of the above works.

From Jerome, epistle 121:

Theophilus, Antiochenae ecclesiae septimus post Petrum apostolum episcopus, quatuor evangelistarum in unum opus dicta compingens, ingenii sui nobis monumenta dimisit.

Theophilus, seventh bishop of the Antiochene church after Peter the apostle, in compiling the sayings of the four evangelists into one work, left us monuments of his ingenuity.

Among the gospels, Theophilus quotes or alludes to Matthew 5.28; Matthew 5.32 = Luke 16.18; Matthew 5.44, 46 = Luke 6.28, 32; Matthew 6.3; and the Johannine prologue.