The interpretation timeline
Romans 16:22 Douay-Rheims

I Tertius, who wrote this epistle, salute you in the Lord.

A.D. 407 – 1871 6 witnesses

Patristic

before A.D. 750
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“"I Tertius, who wrote this Epistle, salute you." This too is no small encomium, to be Paul's amanuensis. Still it is not to pass encomiums on himself that he says this, but that he might attach a warm love to him on their part, for this ministration.”

Scholastic

c. 1100 – 1500
1273
A.D.
Thomas Aquinas Catholic
1225–1274
“After the Apostle has enjoined whom they should greet, he here shows them whom they ought to avoid. And concerning this he does three things. First, he teaches whom they ought to avoid; second, he assigns the reason, at the words for such men, etc.; third, he promises them divine help for accomplishing this, at the words and the God of peace, etc. And because those whom he wished to be avoided proceeded fraudulently, deceiving under the appearance of piety, according to that word of Matthew 7:15: they come to you in sheep's clothing, but inwardly they are ravening wolves, therefore, first, he leads them to exercise caution, saying now I beseech you, brethren, to mark them which cause dissensions and offenses contrary to the doctrine which you have learned. Here, first, it should be considered that "to observe" is nothing other than to consider diligently, which indeed is sometimes taken in a good sense, sometimes in a bad sense. It is taken in a bad sense when someone diligently considers the condition and course of another in order to harm him, according to that word of Psalm 36:12: the sinner shall observe the just man, and shall gnash upon him with his teeth. And in Luke 14:1 it is said: and they watched him. It is taken in a good sense, in one way, when someone considers the precepts of God in order to do them. Exodus 23:21: observe therefore and hear his voice. In another way, when someone diligently considers good men in order to imitate them, according to that word of Philippians 3:17: be followers of me, brethren, and mark them which walk so, as you have us for a pattern. Third, evil men are observed in order to be avoided, and it is taken in this sense here. For there were certain men converted to the faith from among the Jews, who preached that the precepts of the law were to be observed, and from this, first, dissensions and sects followed in the Church, while some of them adhered to the error and others persisted in the true faith. Galatians 5:20: dissensions, sects, etc. Second, offenses and scandals followed, of which it was treated above in chapter 14, while some judged others and others despised others — these are the ones who cause dissensions and offenses. Isaiah 57:14: take away the stumbling-blocks out of the way of my people. Now he says contrary to the doctrine which you have learned from the true apostles of Christ, in order to show that such dissensions and scandals arose from the falsity of their teaching. Galatians 1:9: if any man preach any other gospel unto you than that which you have received, let him be anathema. Second, he warns that, once recognized, they should be avoided, saying and avoid them, that is, flee their doctrine and their company. Psalm 118:115: depart from me, you malignant ones, and I will search the commandments of my God. Then when he says for such men, etc., he assigns two reasons for what he had said, of which the first is taken from the side of those whom he wishes to be avoided. And first he describes their intention, saying for such men do not serve our Lord Christ, but their own belly. For they did not preach for the glory of Christ, but for gain, so as to fill their own belly. Philippians 3:18: many walk, of whom I have told you often, and now tell you even weeping, that they are the enemies of the cross of Christ, whose God is their belly. Second, he describes their deception, saying and by good words and fair speeches deceive the hearts of the innocent, that is, of the simple and unlearned. Proverbs 14:15: the innocent believeth every word. By good words, in which they pretend to sanctity, according to that word of Psalm 27:3: who speak peace with their neighbor, but evils are in their hearts. And fair speeches, namely by which they bless and flatter those who follow them. Isaiah 3:12: O my people, they that call thee blessed, the same deceive thee. Malachi 2:2: I will curse your blessings. He assigns the second reason from the condition of the Romans, who showed themselves ready to follow after both good and evil. Hence, first, he commends them for their readiness for good, saying for your obedience, by which you readily obeyed the faith, is come abroad unto all men, because of the dominion which the Romans then held over the other nations. Hence what was done by the Romans was readily spread abroad to others. Above, in chapter 1:8: your faith is spoken of throughout the whole world. I am glad therefore on your behalf, namely because you have obeyed the faith, and this in charity, of which it is said in 1 Corinthians 13:6, that it rejoiceth not in iniquity, but rejoiceth with the truth. Second, he makes them cautious against evil, saying but yet I would have you wise unto that which is good, namely that you cleave to that which is good — 1 Thessalonians, the last chapter: hold fast that which is good — and simple concerning evil, namely lest through some simplicity you decline toward evil, so that your simplicity may be such that you deceive no one unto evil. Matthew 10:16: be ye wise as serpents, and simple as doves. Conversely, of certain men it is said in Jeremiah 4:22: they are wise to do evil, but to do good they have no knowledge. Then when he says and the God of peace, etc., he promises them divine help against such deceivers. And first the promise is set down, when he says and the God of peace, that is, its author, who hates the dissensions that these men cause, shall bruise Satan, that is, the Devil who through these pseudo-apostles strives to deceive you, under your feet, because indeed you will conquer him through your wisdom. And this shall happen shortly, namely at my coming. Luke 10:19: behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy. Malachi, the last chapter: you shall tread down the wicked, when they shall be as ashes under the sole of your feet. Second, the prayer for obtaining this is set down, when he says the grace of our Lord Jesus Christ be with you, which indeed suffices to protect you. 2 Corinthians 12:9: my grace is sufficient for thee. Then when he says Timothy my workfellow saluteth you, etc., he greets them on behalf of others, saying Timothy my workfellow saluteth you, namely in the preaching of the Gospel. 1 Corinthians 4:17: I have sent unto you Timotheus, who is my beloved son, and faithful, etc. He adds, moreover, and Lucius, and Jason, and Sosipater, my kinsmen, who were Jews, greet you, namely. Now there was a certain notary of Paul named Tertius, to whom Paul granted that he should greet the Romans in his own person. Hence it is added I Tertius, who wrote this epistle, salute you in the Lord. Then he says Gaius mine host saluteth you, to whom the third canonical epistle of John is addressed, in which he is commended for the charity which he showed to the saints. And of the whole church, namely which was gathered in his house, or which was in that province. Then he says Erastus the chamberlain of the city saluteth you, namely he who kept the common chest, that is, the common revenues of the city, and Quartus a brother, that is, a believer, by name Quartus. Then he greets them on his own behalf, saying the grace of our Lord Jesus Christ be with you all. Amen. And he ends the epistle with an act of thanksgiving, saying now to him, namely to God who is the Trinity, that is of power to establish you — 1 Peter, the last chapter: after that ye have suffered a while, he himself shall perfect, confirm, and establish you — and this in the faith which is according to my Gospel, that is, according to the Gospel which I preach. 1 Corinthians 15:11: whether it were I or they, so we preach, and so ye believed. And also according to the preaching of Jesus Christ, who first preached the Gospel, according to that word of Hebrews 2:3: which at the first began to be spoken by the Lord. Hence it is said in Matthew 4:23, that Jesus went about preaching the gospel of the kingdom. Now it is added, according to the revelation of the mystery, that is, of the secret, which indeed can be referred to what he had said above, according to my Gospel; or because in the Gospel itself the secret of the divine incarnation is revealed, according to that word above in chapter 1:17: the righteousness of God is revealed therein; or because to the Apostle himself the Gospel was revealed. 1 Corinthians 2:10: but unto us God hath revealed them by his Spirit. Concerning this secret it is said in Isaiah 24:16: my secret to myself. Or this may better be referred to what he had said, to establish, as if he were saying: God can establish you in my Gospel and preaching, and this according to the revelation of the mystery, that is, of the secret, namely concerning the conversion of the Gentiles, as is found in Ephesians 3:8 and following: unto me, who am less than the least of all saints, is this grace given, that I should preach among the Gentiles, and make all men see what is the dispensation of the mystery, etc. Hence he also adds since the world began, because indeed it was hidden among men that the Gentiles were to be converted to the faith. Now he calls these times eternal as if long-enduring, because from the beginning of the world this was hidden, as also is said in Psalm 75:4: thou, enlightening wonderfully from the everlasting mountains. And it can be said that the eternal times are called eternity itself, of which it is said in Isaiah 57:15: the high and eminent one, inhabiting eternity, so that just as the simple essence of God is described by a certain likeness through corporeal dimensions, according to that word of Job 11:9: the measure thereof is longer than the earth, and broader than the sea, so also his simple eternity is designated through eternal times, insofar as it contains all times. Now he adds that, namely the mystery, is now made manifest, concerning the conversion of the Gentiles, by the scriptures of the prophets, that is, according as the prophets foretold, as was made clear above in chapter 15. Hence in Ephesians 3:5 and following it is said: which in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit, that the Gentiles should be fellow-heirs, etc. Now it is made manifest through the fulfillment of the work by the command of God. Hence according to the commandment of the everlasting God, who indeed by his eternal purpose does in time the things which he wills, which command of God indeed is made known to all nations for the obedience of faith, that is, that all nations may obey the faith. Above, in chapter 1:5: for obedience to the faith among all nations. But if we speak of the mystery of the incarnation, the text is to be construed thus: of the mystery, I say, kept secret since the world began, because before it was not so manifest. Which mystery, I say, is now made manifest by the scriptures of the prophets, who foretold this according to the commandment of the everlasting God, who willed the mystery of the incarnation to be made manifest, and this for the obedience of faith among all nations. Of the mystery, I say, although kept secret among men, yet known only to God who is wise, because he alone knew this, and those to whom he willed to reveal it, because, as it is said in 1 Corinthians 2:11: the things of God knoweth no man, but the Spirit of God. Or it can be understood of him who alone is wise, namely by essence, as is said in Matthew 19:17 and Mark 10:18: none is good, save one, that is, God. Nor is the Son excluded by this, because the perfection of the whole Trinity is the same, just as, conversely, it is said: no man knoweth the Father, save the Son, Matthew 11:27 — the Father is not excluded from knowledge of himself. Now he adds by Jesus Christ; which is not to be understood in this sense, that God the Father is wise through Jesus Christ, because since for God to be wise is the same as to be, it would follow that the Father exists through the Son, which is unfitting; but this is to be referred to what he had said above: is now made manifest, namely through Jesus Christ. To whom, that is, to Jesus Christ, be honor and glory, through the reverence of the whole creature, according to that word of Philippians 2:10: at the name of Jesus every knee should bow. And glory, namely as to the fullness of his divinity, just as it is added there: and every tongue should confess that the Lord Jesus Christ is in the glory of God the Father. And this not for a time, but for ever, world without end. Hebrews, the last chapter: Jesus Christ, the same yesterday, and today, and forever. He adds, moreover, for the confirmation of the truth: Amen. Or it can be construed thus: known only to the wise God, to whom, through Jesus Christ, is glory — who glorified God, according to that word of John 17:4: I have glorified thee on the earth. Now it should be noted that this construction is defective, and is to be supplied thus: to him who is able, etc., be honor and glory through Jesus Christ, to whom is honor and glory. But if the word "to whom" is not there, the construction will be straightforward.”

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“Gaius mine host,.... There was one Gaius a Macedonian, that was with the apostle at Ephesus, Act 19:29; and another Gaius of Derbe, that accompanied him into Asia, Act 20:4; whether either of these, as the latter seems more probable, was this person, is not certain. However, it seems very likely that it is the same Gaius the apostle baptized at Corinth, Co1 1:14; and some have thought him to be the same that the Apostle John wrote his third epistle to, and indeed the characters of hospitality and generosity there given him well agree with this, who was not only the apostle's host that entertained him in a kind and liberal manner, but of all the saints: and of the whole church, saluteth you; that is, of the church at Corinth, to whom he was kind and hospitable, even to as many as stood in need of his assistance; or of the church of Christ in general, being beneficent and liberal to all Christian strangers that came that way, lodged them at his house, and provided every thing proper and convenient for them. Dr. Lightfoot thinks that there was a public hospital or receptacle for strangers at Corinth, in imitation of the Jews, who had a place adjoining to their synagogues to entertain travellers in; and that Gaius was the chief officer and overseer of this house, who, discharging his trust well, is deservedly commended. That the Jews had places near their synagogues for such a purpose is, certain. It is said (b), "why do they sanctify (or consecrate the day?) that travellers may do their duty, who eat, and drink, and sleep in the synagogue.'' The gloss on it is, "not the synagogue itself, but the chambers which were near the synagogue, are called the synagogue, and from thence they heard the consecration.'' And elsewhere (c) it is said, "in the synagogues they neither eat nor drink--but there is a place near the synagogue where travellers used to sleep and eat;'' and then follows what is said before. And Maimonides (d) observes, "there is no sanctification (of the sabbath) but in the place where the meal is eaten; so a man may not sanctify in one house, and eat in another; but if he sanctifies in this, he must eat in this; but why do they sanctify in the synagogue? because of travellers who eat and drink there.'' Upon which his commentator remarks (e), that "they do not eat in the synagogue at all, but they eat, , "in a house near the synagogue", where they sit at the time of hearing the sanctification.'' But whether there was such an house at Corinth near the place of public worship, or any where else for this purpose, is not certain; and to make Gains only an overseer over such an house, though a faithful one, greatly sinks his character; since one would conclude from hence, that his entertainment of the apostle, and other saints, was at his own expense. Erastus the chamberlain of the city saluteth you; whom the apostle is said to leave at Corinth, Ti2 4:20, and at another time to send along with Timotheus into Macedonia, if the same person is intended; for these do not seem so well to accord with his being in such an office, which must require attendance, and would not admit of going from place to place with the apostle, or of being sent by him. The city, of which he was chamberlain, was the city of Corinth, where the apostle and this Erastus were, when this epistle was wrote. The word translated "chamberlain", is often used for a steward; and here it signifies such an officer as had the care of the city chest or coffer, and distributed the public money; and seems to answer to the "quaestor urbanus", or city treasurer, among the Romans, whose business it was to receive the city accounts, and disburse at all occasions of public expenses; so that this was a place of honour and trust; hence it appears, that though not many, yet some rich and honourable were called by grace, and embraced the Gospel. His name signifies beloved, and is the same with David in Hebrew. What nation he was of is not certain, whether a Roman, a Greek, or Jew; one of this name is reckoned among the seventy disciples, and it said to be bishop of Paneas, or of the Philippians; See Gill on Luk 10:1. Quartus a brother; not of Tertius, nor of Erastus, nor of the apostle according to the flesh, as some have thought, but a brother in a spiritual relation. This man, as appears from his name, was a Roman; probably had before lived at Rome, and therefore sends his salutations to the Christians there: he is mentioned among the seventy disciples, and said to be bishop of Berytus; See Gill on Luk 10:1. (b) T. Bab. Pesachim, fol. 101. 1. (c) Gloss. in T. Bab. Bava Bathra, fol. 3. 2. (d) Hilchot Sabbat, c. 29. sect. 8. (e) Maggid. Misnah in ib.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“I Tertius, who wrote this epistle - Some eminent commentators suppose Tertius to be the same with Silas - the companion of St. Paul. If this were so, it is strange that the name which is generally given him elsewhere in Scripture should not be used in this place. I have already noticed (Preface) that some learned men have supposed that St. Paul wrote this epistle in Syriac, and that Tertius translated it into Greek; but this can never agree with the declaration here: I Tertius, who wrote, γραψας την επιστολην, this epistle; not translated or interpreted it. It appears that St. Paul dictated it to him, and he wrote it down from the apostle's mouth; and here introduces himself as joining with St. Paul in affectionate wishes for their welfare. Salute you in the Lord - I wish you well in the name of the Lord: or, I feel for you that affectionate respect which the grace of the Lord Jesus inspires. It is not clear whether the two following verses be the words of Tertius or St. Paul.”
Source
1849
A.D.
1774–1849
“This Tertius was the amanuensis, or secretary of St. Paul, and wrote this epistle as St. Paul dictated. It is not on that account less divinely inspired than the rest. (Estius)”
1871
A.D.
1871
“I, Tertius, who wrote this--"the" epistle--as the apostle's amanuensis, or penman. salute you in the Lord--So usually did the apostle dictate his epistles, that he calls the attention of the Galatians to the fact that to them he wrote with his own hand (Gal 6:11). But this Tertius would have the Romans to know that, far from being a mere scribe, his heart went out to them in Christian affection; and the apostle, by giving his salutation a place here, would show what sort of assistants he employed.”
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.