The interpretation timeline
2 Thessalonians 3:17 Douay-Rheims

The salutation of Paul with my own hand; which is the sign in every epistle. So I write.

A.D. 407 – 1871 6 witnesses 7 excerpts

Patristic

before A.D. 750
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“Whence then shall we know them, he says? For this very reason, he added, "The salutation of me Paul with mine own hand, which is the token in every Epistle: so I write. The grace of our Lord Jesus Christ be with you all." He does not here mean, that this is the token,-for it is probable that others also imitated this,-but that I write the salutation with mine own hand, as is the custom also now among us. For by the subscription the writings of those who send letters are made known.”
Source
“"The salutation of me Paul with mine own hand, which is the token in every Epistle: so I write. The grace of our Lord Jesus Christ be with you all." This he says that he writes in every Epistle, that no one may be able to counterfeit them, his subscription being subjoined as a great token. And he calls the prayer a salutation, showing that everything they then did was spiritual; even when it was proper to offer salutation, the thing was attended with advantage; and it was prayer, not merely a symbol of friendship. With this he began, and with it he ended, guarding with strong walls what he had said elsewhere, and laying safe foundations, he brought it also to a safe end. "Grace be unto you and peace," he says; and again, "The grace of our Lord Jesus Christ be with you all. Amen." This the Lord also promised, saying to His disciples, "Lo, I am with you alway, even unto the end of the world." But this takes place when we are willing. For He will not be altogether with us, if we place ourselves at a distance. "I will be with you," He says, "always." Let us not therefore drive away grace.”
Source

Scholastic

c. 1100 – 1500
1272
A.D.
Thomas Aquinas Catholic
1225–1274
“Above, the Apostle showed what he handed on to them by his own example, namely that they should not be restless, but that they should work; here he shows how he handed this on in the present passage by words and by deeds. Hence he says *when we were*, as if to say: that we might give you a model, we did what we taught, because we declared this, that, etc. These words, as the Gloss says, and Augustine in the book *On the Works of Monks*, certain men were perverting, to mean that it is not lawful for the servants of God to work with their hands, on account of what is said in Matthew 6:34: *be not solicitous*, etc. For they say that this work pertains to solicitude for sustenance. And on account of this they referred this to spiritual works; as if to say: if anyone does not want to do meritorious and spiritual works, he is not worthy to eat. But this is against the intention of the Apostle, who says *we declared* that we ourselves did so, namely in labor and weariness. But what is the meaning of *because if anyone does not want*, etc.? Is this a counsel or a precept? And it seems to be a precept, because below it is said: *if anyone does not obey our word*, etc. Therefore all are bound to work with their hands. Whoever therefore does not work with his hands, but stands idle, sins mortally. I answer. It must be said that it is a precept, but a thing is commanded in two ways: simply, or under a condition. That which is of itself necessary for salvation is commanded simply, and these are the works of the virtues. But under a condition, as when such is the case that the precept cannot be kept without manual work. Now it is commanded to man that he sustain his own body, for otherwise he is a murderer of himself. Genesis 2:16: *of every tree of Paradise you may eat*, etc. By precept, therefore, man is bound to nourish his own body, and likewise we are bound to all the things without which the body cannot live. Hence whoever does not have another means by which to sustain his body lawfully, either by possession or by lawful business, is bound to labor, lest he steal. Ephesians 4:28: *he who stole, let him now steal no more, but rather let him labor, working with his hands*, etc. It is therefore a precept, when one cannot otherwise live lawfully. Hence he says *if anyone does not want to work, neither let him eat*. One or the other of two things is therefore necessary, that a man may eat, namely either that he have a possession, or that he procure it lawfully. Psalm 127:2: *the labors of your hands, for you shall eat*, etc. 1 Thessalonians 4:11: *work with your hands, as we commanded you*, etc. Then when he says *we have heard*, etc., he sets forth the necessity of this precept, because the Apostle says this not so much from the office of a teacher, as on account of a vice of the people. Therefore first he sets forth the fault which induces the necessity of the precept; second he applies a remedy, at the place *but to those who*, etc. He says therefore *we have heard*, etc.; as if to say: therefore I do not conceal this precept, because we have heard that certain ones, etc. For the soul of man must always be occupied about something, and therefore it is necessary that the idle suffer restlessness about unlawful things. 1 Thessalonians 4:11: *give heed that you be quiet*, etc. And he adds *but acting curiously*, namely about the affairs of others. Proverbs 21:25: *desires kill the slothful*. Then he applies a remedy, when he says *but to those who*, etc. And first on the part of those sinning, second on the part of the others, at the place *but you*, etc. He says therefore, to those who are of this sort *we declare* — severely, as a prelate — and *we beseech* — charitably, as their father — that their own bread, not another's but owed to them, namely lawfully acquired, *with silence*, that is, without restlessness, not running about, they eat. Isaiah 30: the cultivation of justice is silence. Ezekiel: idleness taught much malice. Then when he says *but you*, etc., on the part of the others not sinning he applies a twofold remedy. First, namely, that they not cease from doing good; second, that they correct those men, at the place *but if anyone*, etc. He says therefore *but you*, etc., as if to say: do not fail in doing good, even though the idle abuse it. Galatians 5: *doing good, let us not fail*, etc. And this is necessary, even if they should work with their hands, and nothing should be lacking to them, because assistance to others is necessary. Then when he says *but if anyone*, etc., he signifies that they be corrected, and first he shows in what order they are punished; second he shows the effect of the punishment, at the place *that they may be ashamed*; third the end, at the place *and do not*, etc. As to the order indeed: first, he sets forth the fault, second its manifestation, third its punishment. The fault is disobedience; and therefore he says *but if anyone does not obey*. 1 Kings 15:23: *to resist is as it were the sin of divination, and to be unwilling to acquiesce is as it were the crime of idolatry*. The manifestation and the conviction is set forth, when he says *note this man by an epistle*, that is, make him manifest, but through an inquiry into the truth. Job 29:16: *the cause which I did not know, I investigated most diligently*. Their punishment is the sentence of excommunication; hence he says *and do not mingle with him*, etc. 1 Corinthians 5:11: *with such a one not even to take food*. 2 John, v. 10: *do not receive him into the house, nor say to him, hail*. Here note that excommunication is inflicted for disobedience; he must, however, be convicted. Hence he says *if anyone does not obey*, by your epistle, *note this man*, that is, signify him to us, that he may be punished; and yet you meanwhile are not to mingle with him. But the effect of the punishment is that he be ashamed, and from this come to his senses. Ecclesiasticus 4:25: *there is a shame that brings sin, and there is a shame that brings glory*. But the end and intention ought to be his correction, which charity intends; hence he says *and do not regard him as*, because it ought not to be done out of the rancor of hatred, but out of zeal for charity; as if to say: let your avoiding of him not be done out of the hatred of enmity. Matthew 5:44: *love your enemies, do good to those who hate you*. And therefore he says *but correct him as a brother*. In which charity is shown. Psalm 132:1: *behold how good, and how pleasant it is for brothers to dwell in one*, etc. Then when he says *but he himself*, etc., he concludes the epistle. And first the conclusion is set forth; second the salutation, which is as it were the seal of the epistle, at the place *the salutation*, etc. Again the first is divided into two, because he first wishes them the gifts of God, second God himself, at the place *the Lord be*, etc. As to the first he says *he himself*, etc. God is said to be of peace with respect to two things. For peace consists in two things, namely that a man be in concord with himself, and with others. And neither can be had sufficiently except in God: because he is not in concord with himself sufficiently except in God, and less so with others, because then the affection of man is in concord within itself when that which is desired according to one thing suffices with respect to all, which nothing can be except God. Psalm 102:5: *who fills your desire with good things*. For whatever other things, besides God, do not suffice for all, but God suffices. John 16:33: *in me you shall have peace*, etc. Likewise men are not united among themselves, except in that which is common among them, and this is above all God. And therefore he says *may the God of peace give* — not a temporal peace, but an everlasting one, that is, a spiritual one, which begins here, and is perfected there. Psalm 147:3: *who has placed peace as your borders*, etc. And this *in every place*, and in the whole world among the faithful. As to the second he says *the Lord be with you all*, because nothing else is well possessed, unless he himself be possessed through faith and charity. *My salutation*, he says this on account of unfaithful men perverting his epistles. Galatians, last chapter: *see with what letters I have written to you with my own hand*, etc. *Which is a sign*, etc. *Grace*, that is, the gratuitous gift of God, which renders you pleasing to God, etc. John 1:17: *grace and truth came through Jesus Christ*.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“The salutation of Paul with mine own hand,.... In writing his epistles, the body and substance of them he used an amanuensis, but the salutation he wrote with his own hand: which is the token in every epistle; by which they might be known to be true and genuine, and be distinguished from counterfeit ones: and the rather he mentions this, that they might be troubled neither by word, nor by spirit, nor by epistle, as from them, as they had been, Th2 2:2 for it seems that this wicked practice of counterfeiting the epistles of the apostles, or carrying about spurious ones, under their name, began so early; to prevent which, the apostle took this method, so I write, as follows:”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“The salutation of Paul with mine own hand - It is very likely that Paul employed an amanuensis generally, either to write what he dictated, or to make a fair copy of what he wrote. In either case the apostle always subscribed it, and wrote the salutation and benediction with his own hand; and this was what authenticated all his epistles. A measure of this kind would be very necessary if forged epistles were carried about in those times. See the note on Co1 16:21, and see Col 4:18 (note).”
Source
1849
A.D.
1774–1849
“The salvation of, &c. The apostle gives them this caution, for fear the faithful might be deceived by fictitious letters. For they had already received one of this kind, which had terrified them, by foretelling that the day of judgment was at hand. This deception he is here anxious to remove, signing the present communication with his own hand, and sealing it with his own seal. For although the rest of the epistle had been written by another, these words to the end were written by himself. (Estius) — All the civilities of this great doctor of grace terminate in wishing it to his friends. This is his genuine character, because it is the love and continual effusion of his heart. (Bible de Vence) — Amen. This the congregation added after the epistle had been read, and from this circumstance alone has it found a place here. (Polus synopsis Criticorum, p. 1003, vol. 4.) Bible Text & Cross-references: He begs their prayers, and warns them against idleness. 1 For *the rest, brethren, pray for us, that the word of God may run and may be glorified, even as among you: 2 And that we may be delivered from troublesome and evil men: for all men have not faith. 3 But God is faithful, who will strengthen and keep you from evil. 4 And we have confidence concerning you in the Lord, that the things which we command, you both do, and will do. 5 And the Lord direct your hearts, in the charity of God, and in the patience of Christ. 6 And we charge you, brethren, in the name of our Lord Jesus Christ, that you withdraw yourselves from every brother walking disorderly, and not according to the tradition which they have received of us. 7 For yourselves know how you ought to imitate us: for we were not disorderly among you: 8 *Neither did we eat any man’s bread for nothing, but in labour and in toil working night and day, lest we should be burthensome to any of you. 9 Not as if we had not power; but that we might give ourselves a pattern to you to imitate us. 10 For also when we were with you, we declared this to you, that if any man will not work, neither let him eat. 11 For we have heard that there are some among you who walk disorderly, working not at all, but curiously meddling. 12 Now we charge them that are such, and beseech them by the Lord Jesus Christ, that working with silence, they would eat their own bread. 13 *But you, brethren, be not weary in well-doing. 14 And if any man obey not our word by this epistle, note that man, and do not keep company with him, that he may be ashamed: 15 Yet do not esteem him as an enemy, but admonish him as a brother. 16 Now the Lord of peace himself, give you everlasting peace in every place. The Lord be with you all. 17 The salutation of Paul with my own hand: which is the sign in every epistle: so I write. 18 The grace of our Lord Jesus Christ be with you all. Amen.”
Source
1871
A.D.
1871
“The Epistle was written by an amanuensis (perhaps Silas or Timothy), and only the closing salutation written by Paul's "own hand" (compare Rom 16:22; Co1 16:21; Col 4:18). Wherever Paul does not subjoin this autograph salutation, we may presume he wrote the whole Epistle himself (Gal 6:11). which--which autograph salutation. the token--to distinguish genuine Epistles from spurious ones put forth in my name (Th2 2:2). in every epistle--Some think he signed his name to every Epistle with his own hand; but as there is no trace of this in any manuscripts of all the Epistles, it is more likely that he alludes to his writing with his own hand in closing every Epistle, even in those Epistles (Romans, Second Corinthians, Ephesians, Philippians, First Thessalonians) wherein he does not specify his having done so. so I write--so I sign my name: this is a specimen of my handwriting, by which to distinguish my geniune letters from forgeries.”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.