Demetrius hath good report of all men, and of the truth itself: yea, and we also bear record; and ye know that our record is true. Demetrius hath good report - Perhaps another member of the Church where Caius was; or he might have been one of those whom the apostle recommends to Caius; or, possibly, the bearer of this letter from John to Caius. He seems to have been an excellent person: all testified of his righteousness; the truth - Christianity, itself bore testimony to him; and the apostles themselves added theirs also.
Related Commentaries of 3 John 1:12
3 John 1:12
12 Demetrius hath good report of all men, and of the truth itself: yea, and we also bear record; and ye know that our record is true.