The interpretation timeline
Acts 15:23 Douay-Rheims

Writing by their hands: The apostles and ancients, brethren, to the brethren of the Gentiles that are at Antioch, and in Syria and Cilicia, greeting.

A.D. 215 – 1871 8 witnesses

Patristic

before A.D. 750
215
A.D.
c. A.D. 150–215
“The twelve, having called together the multitude of the disciples, said, "It is not meet for us to leave the word of God and serve tables." If they avoided this, much more did they shun gluttony. And the apostles themselves, writing to the brethren at Antioch, and in Syria and Cilicia, said: "It seemed good to the Holy Ghost, and to us, to lay upon you no other burden than these necessary things, to abstain from things offered to idols, and from blood, and from things strangled, and from fornication, from which, if you keep yourselves, ye shall do well." But we must guard against drunkenness as against hemlock; for both drag down to death.”
Source
date
unknown
c. A.D. 380
“Then it seemed good to us the apostles, and to James the bishop, and to the elders, with the whole Church, to send men chosen from among our own selves, with Barnabas, and Paul of Tarsus, the apostle of the Gentiles, and Judas who was called Barsabbas, and Silas, chief men among the brethren, and wrote by their hand, as follows: "The apostles, and elders, and brethren, to the brethren of Antioch, Syria, and Cilicia of the Gentiles, send greeting: Since we have heard that some from us have troubled you with words, subverting your souls, to whom we gave no such commandment, it has seemed good to us, when we were met together with one accord, to send chosen men to you, with our beloved Barnabas and Paul, men that have hazarded their lives for our Lord Jesus Christ, by whom ye sent unto us. We have sent also with them Judas and Silas, who shall themselves declare the same things by mouth. For it seemed good to the Holy Ghost, and to us, to lay no other burden upon you than these necessary things; that ye abstain from things offered to idols, and from blood, and from things strangled, and from fornication: from which things if ye keep yourselves, ye shall do well. Fare ye well."”
Source
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"The Apostles and elders and brethren send greeting unto the brethren which are of the Gentiles in Antioch and Syria and Cilicia." "To those in Antioch," it says, "and Syria and Cilicia," where the disease had its birth. Observe how they say nothing harsher against those brethren, but look to one thing only, namely, to undo the mischief which has been done. For this would make even the movers of the faction there to confess that they were wrong. They do not say, The seducers, the pestilent fellows, or suchlike: though where need is, Paul does this, as when he says, "O full of all guile": but here, the point being carried, there was no need.”
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“And wrote letters by them after this manner,.... Not that they made use of them as their amanuenses, to write their letters for them; but being written they put them into their hands, and sent them by them, and they were written in the following form: the apostles, and elders, and brethren; which belonged to, or were members of the church at Jerusalem; they are severally set in their proper place and order: the apostles, Peter, and James, and John, and it may be some others first; for these God had set in the first place in the church; then the elders, or preachers of the Gospel, such as were Judas and Silas: and then the brethren, or private members of the church; who are called so, because they are of one family, and have one Father, and are partakers of the same grace and privileges: these, send greeting; or their Christian salutation, wishing all peace and prosperity, both for soul and body, temporal, spiritual and eternal: unto the brethren which are of the Gentiles in Antioch, and Syria and Cilicia; the brethren or members of the several churches in these parts, who were Gentiles, are particularly sent to; and not the brethren who were Jews; because they were especially concerned, and to them is the advice directed: Antioch is first mentioned, that being the place where the controversy began; but there being other churches in Syria, besides Antioch, in which were many Gentiles, and also in Cilicia, and particularly at Tarsus, Paul's native place, and where he had preached, Act 9:30 they are therefore mentioned, and being countries near to one another, it is very likely that the controversy had spread itself among them.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“Send greeting unto the brethren - of the Gentiles - There was no occasion to send such a letter to the brethren which were of the Jews, because that law which had been so long read in their synagogues taught them all those things; and therefore the epistle is sent exclusively to the Gentiles. The word greeting is in the original χαιρειν, to be well, to be safe; a very usual form in Greek epistles, the word ευχομαι being understood, I wish thee to be well.”
Source
1849
A.D.
1774–1849
“The brethren of the Gentiles. Hence we see, that the letter, with the decree of the Council, only regarded those converts, who had been Gentiles; neither are they forbidden to use the Jewish ceremonies, but a declaration is made, that they have no obligation to follow the said ceremonies and precepts, as it will appear by other places. (Witham)”
Source
1871
A.D.
1871
“And they wrote . . . by them--This is the first mention in the New Testament history of writing as an element in its development. And the combination here of written and oral transmission of an important decision reminds us of the first occasion of writing mentioned in the Old Testament, where a similar combination occurs (Exo 17:14). But whereas there it is the deep difference between Israel and the Gentiles which is proclaimed, here it is the obliteration of that difference through faith in the Lord Jesus [BAUMGARTEN]. greeting--The only other place in the New Testament where this word occurs (except in the letter of Lysias, Act 23:26) is Jam 1:1, which seems to show that both letters were drawn up by the same hand [BENGEL]. the Gentiles in Antioch, and Syria, and Cilicia--showing that churches then existed in Cilicia as well as Syria, which owed their existence, in all likelihood, to Paul's labors during the interval between his return to Tarsus (Act 9:30) and his departure in company with Barnabas for Antioch (see on Act 11:25).”
Source

Undated

date unknown
date
unknown
Glossa Ordinaria Medieval
“The apostles and the ancients. The common title of the apostles is set first, lest any occasion of dissension be left. To the brethren of the Gentiles. The first benefit of the style is that the apostles call the Gentiles brethren, that is, sons of the one God. Greeting. An ellipsis, because for the breadth of charity every word is too narrow, and therefore no word is set down, that they may be understood to wish them all good things at once.”
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.