Titus 1:4

4. Own son Literal Greek, genuine or legitimate son; son, that is, by regeneration, as Paul does not hesitate to call even the humble Onesimus son, as being under his ministry converted. Genuine son, as being in his own true spiritual likeness; begotten to the Pauline gospel, and competent to represent and establish it in Crete. Extended as is his own style and title, that assigned to Titus is brief and simple. Note, 1 Timothy 1:2. Yet, as son, Titus seems to be made heir to a very full amount of apostolic authority, as appears in the very strong terms conveying functions in this epistle and in this chapter. Even if it could be supposed that Timothy was appointed pastor of but a single Church in Ephesus, Titus was certainly a super-presbyterial superintendent of several Churches, with their pastors, in Crete. He was, however, more an itinerant bishop than a diocesan.

Common faith Common to all the elect, Titus 1:1. The sonship of Titus was not after the flesh, but after the faith.

Grace Note 1 Timothy 1:2.