The interpretation timeline
Galatians 6:16 Douay-Rheims

And whosoever shall follow this rule, peace on them, and mercy, and upon the Israel of God.

A.D. 407 – 1871 6 witnesses

Patristic

before A.D. 750
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"For neither is circumcision any thing, nor uncircumcision, but a new creature. And as many as shall walk by this rule, peace be upon them, and mercy, and upon the Israel of God." Observe the power of the Cross, to what a pitch it hath raised him! not only hath it put to death for him all mundane affairs, but hath set him far above the Old Dispensation. What can be comparable to this power? for the Cross hath persuaded him, who was willing to be slain and to slay others for the sake of circumcision, to leave it on a level with uncircumcision, and to seek for things strange and marvellous and above the heavens. This our rule of life he calls "a new creature," both on account of what is past, and of what is to come; of what is past, because our soul, which had grown old with the oldness of sin, hath been all at once renewed by baptism, as if it had been created again. Wherefore we require a new and heavenly rule of life. And of things to come, because both the heaven and the earth, and all the creation, shall with our bodies be translated into incorruption. Tell me not then, he says, of circumcision, which now availeth nothing; (for how shall it appear, when all things have undergone such a change?) but seek the new things of grace. For they who pursue these things shall enjoy peace and amity, and may properly be called by the name of "Israel." While they who hold contrary sentiments, although they be descended from him (Israel) and bear his appellation, have yet fallen away from all these things, both the relationship and the name itself. But it is in their power to be true Israelites, who keep this rule, who desist from the old ways, and follow after grace.”
Source
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“Paul means those who are truly prepared for the vision of God. These are distinguished from those who are called by this name [Israel] and in their carnal blindness refuse to see the Lord, spurning his grace, still desiring to be enslaved by temporal things.”

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“Having disclosed the intention of the seducers, and having intimated his own, here the Apostle consequently admonishes them: first, to the imitation of himself; second, that they cease from troubling him, at the place "from now on let no one," etc.; third, he implores for them the help of grace for the fulfillment of the aforesaid things. He says therefore first: my intention is that I glory in nothing but the cross of Christ, which you also ought to do, because whoever shall have followed this rule — namely, the one that I hold — that is, this rectitude of glorying. 2 Corinthians 10:13: "we do not glory beyond measure, but according to the measure of the rule," etc. Peace be upon them — namely, upon those who glory, because they glory in nothing but Christ. Peace, I say, by which they may be set at rest and perfected in good. For peace is the tranquility of the mind. Song of Songs 8:10: "since I became before him as one finding peace." Colossians 3:15: "let the peace of Christ exult in your hearts, in which," etc. And mercy, by which they may be freed from sins. Lamentations 3:22: "the mercies of the Lord, that we are not consumed." Wisdom 4:15: "the grace of God and mercy is upon his saints, and regard for his elect" — namely, who are Israel. Romans 2:28: "for he is not a Jew who is one outwardly." He therefore is the Israel of God who is spiritually Israel before God. John 1:47: "behold truly an Israelite, in whom there is no guile." Romans ch. 9:6: "for not all who are of Israel, these are Israelites," etc. But those who are the children of the promise are reckoned in the seed. Hence even the Gentiles themselves were made the Israel of God through rectitude of mind. Israel is interpreted as "most upright." Genesis 32: "Israel shall be your name," etc. Consequently, when he says "from now on let no one," etc., he admonishes them that they cease from troubling him. And first he sets down the admonition; second he assigns the reason for it, at the place: "for I bear the marks." He says therefore "from now on," etc.; which can be expounded in two ways. In one way, so that "de caetero" is taken as the force of a single word, so that the sense is "de caetero," that is, "henceforth." In another way, so that it is taken as the force of two words, so that the sense is: "concerning the rest, let no one," etc.; as if he were to say: I will glory only in the cross; concerning all other things, let no one trouble me, because I care for none of them. But the first is better. Now as to what he says, "let no one trouble me," it can be referred to the false ones, who were troublesome to the Apostle, by raising questions and murmuring about the legal observances. Psalm 34:13: "but I, when they were troublesome to me, was clothed with sackcloth," etc. Or it can be referred to the hearers who were not rightly thinking, so that it is said "let no one trouble me," that is, let no hearer show himself to be such that I again have need of laboring over him — namely, by thinking otherwise than I teach. Now he assigns the reason for these things, saying "for I bear the marks," etc. For "stigmata" properly are certain marks impressed upon someone with a hot iron, as when a slave is marked by some master in the face, so that no one may claim him for himself, but leaves him in peace to his own master, whose marks he bears. In this way too the Apostle says that he bears the marks of the Lord, as though he were marked as a servant of Christ. And this because he bore the insignia of the passion of Christ, suffering for him many tribulations in his own body, according to that word of 1 Peter 2:21: "Christ suffered for us, leaving you an example," etc. 2 Corinthians 4:10: "always bearing about the mortification of the Lord Jesus in our body," etc. And according to this it can be joined to what precedes in two ways. In one way, as has been said, "let no one trouble me," for I bear the insignia of our Lord Jesus Christ in my body, and thus no one has a right over me except Christ. In another way: let no one trouble me, because I have many other conflicts and marks, which trouble me in the persecutions I suffer, and it is grievous to add affliction to the afflicted. Hence Job complains, 16:15: "he has cut me down with wound upon wound." But the first is better. Now he implores the help of the grace of God, saying "the grace of our Lord Jesus Christ," etc. — by which you may be able to fulfill the aforesaid things — "be with your spirit," that is, with your reason, that you may understand the truth. Or "with your spirit," namely, that by which you ought to observe the law, and not carnally. Romans ch. 8:15: "for you have not received," etc.”
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“From henceforth let no man trouble me,.... Having so clearly stated and explained the doctrine of justification, and so largely proved that it is not by works, but by faith, and that circumcision and other rituals of the ceremonial law were not necessary to it, he desires, nay, in an authoritative way he requires, that they give him no further trouble on that head; signifying, that he expected they would be satisfied with what he had wrote, and abide by the truth and obey it, as they had formerly done; that he should hear no more objections from them, or complaints of them: nor need they further inquire his sense of these things; by this they would fully know his faith and practice; as indeed they might also by his suffering persecutions on the account of his faith, and his preaching the Gospel of Christ, and particularly this part of it: for I bear in my body the marks of the Lord Jesus; by which he means, not the marks in Christ's hands, feet, and side; but the reproachful characters the apostle was stigmatized with; or the real scars in his body, made by beating, scourging, and stoning of him; or his sufferings and persecutions in general, which he endured for the sake of Christ and his Gospel; see Co2 11:23. The allusion is either to servants and soldiers, who, when taken into service, used to have some particular mark put upon them, that they might be known to be such an one's servant, or soldier (c); as the Hebrew servant, who was willing to serve his master, had his ear bored through with an awl, Exo 21:6 so the apostle was known to be a firm and faithful servant, and a good soldier of Christ, by the reproaches and afflictions which he underwent for his sake; or else to those marks which, by way of reproach and punishment, were made upon fugitive servants, or soldiers, that deserted; as the sufferings of the apostle were designed as reproaches to him, and punishments of him, for preaching the Gospel of Christ; but these he gloried in, and bore and carried as trophies and marks of honour. Just as veteran soldiers show the scars and wounds they have received in battle, as tokens of their valour and courage, in facing and fighting the enemy in greatest danger: these he is said to bear "in his body"; not in the bodies of others, he gloried not in their flesh, as the false apostles did; nor in the circumcision of his own flesh, the scar that left there the mark of Moses and of a Jew; but in those things which were marks of his being a disciple of Christ, and not of Moses, and which he bore for his sake; and since therefore it was so easy to discern on which side of the question he was, from his suffering persecution for the cross of Christ; and since he had so many and such great trials and exercises, he, with apostolical gravity and authority, commands them to give him no more trouble, from the time of their reception of the epistle, henceforward. (c) Vid. Lydium de re militare, l. 1. c. 6.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“As many as walk according to this rule - Τῳ κανονι τουτῳ· This canon; viz. what is laid down in the preceding verses, that redemption is through the sacrifice of Christ; that circumcision and uncircumcision are equally unavailable; and that none can be saved without being created anew. This is the grand canon or rule in Christianity. Peace be on them - Those who act from this conviction will have the peace and mercy of God; for it is in this way that mercy is communicated and peace obtained. The Israel of God - The true Christians, called here the Israel of God, to distinguish them from Israel according to the flesh. See the notes on Rom 2:29; Rom 4:12 (note).”
Source
1871
A.D.
1871
“as many--contrasting with the "as many," Gal 6:12. rule--literally, a straight rule, to detect crookedness; so a rule of life. peace--from God (Eph 2:14-17; Eph 6:23). mercy-- (Rom 15:9). Israel of God--not the Israel after the flesh, among whom those teachers wish to enrol you; but the spiritual seed of Abraham by faith (Gal 3:9, Gal 3:29; Rom 2:28-29; Phi 3:3).”
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.