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Demetrius hath good report of all [men], This man was of a quite different cast from Diotrephes, and therefore the apostle makes mention of him to Gaius, to be followed by him, and not the other; he was either the same with Demas, which is a contraction of this name, or the person that John sent from Ephesus with this letter: we read of an Ephesian of this name, Acts 19:24; though not the same person; or else one that also was a member of the same church with Gaius and Diotrephes; and he being kind and beneficent, obtained a good report of the generality of men, not only of the brethren, but of those that were without; for a liberal man is universally respected. The Syriac version adds, "and of the church itself"; as distinct from all men, or the generality of the men of the world:

and of the truth itself; that is, whoever speaks truth must give him a good character, for this cannot be understood with any propriety of the Gospel, nor of Jesus Christ:

yea, and we also bear record; or a testimony to the character of Demetrius; that is, I, John, the apostle, and the saints at Ephesus:

and ye know that our record is true; faithful, and to be depended upon. The Alexandrian copy, and several others, read, "thou knowest", as does also the Vulgate Latin version, which seems most agreeable, since this epistle is directed to a single person; compare this with John 19:35; and it will give a further proof of this epistle being the Apostle John's.

Demetrius hath good report of all men - Little is known of Demetrius. Lucke supposes that he resided near the place where the author of this Epistle lived, and was connected with the church there, and was probably the bearer of this Epistle. It is impossible to determine with certainty on this point, but there is one circumstance which seems to make it probable that he was a member of the same church with Gaius, and had united with him in showing Christian hospitality to these strangers. It is the use of the phrase “hath good report of all,” implying that some testimony was borne to his character beyond what the writer personally knew. It is possible, indeed, that the writer would have used this term respecting him if he lived in the same place with himself, as expressing the fact that he bore a good character, but it is a phrase which would be more appropriately used if we suppose that he was a member of the same church with Gaius, and that John means to say than an honorable testimony was borne of his character by all those brethren, and by all others as far as he knew.

And of the truth itself - Not only by men, who might possibly be deceived in the estimate of character, but by fact. It was not merely a reputation founded on what “appeared” in his conduct, but in truth and reality. His deportment, his life, his deeds of benevolence, all concurred with the testimony which was borne by men to the excellency of his character. There is, perhaps, particular reference here to his kind and hospitable treatment of those brethren.

Yea, and we also bear record - John himself had personally known him. He had evidently visited the place where he resided on some former occasion, and could now add his own testimony, which no one would call in question, to his excellent character.

And ye know that our record is true - This is in the manner of John, who always spoke of himself as having such character for truth that no one who knew him would call it in question. Every Christian should have such a character; every man might if he would. Compare the notes at John 19:35; John 21:24.