The interpretation timeline
Romans 16:18 Douay-Rheims

For they that are such, serve not Christ our Lord, but their own belly; and by pleasing speeches and good words, seduce the hearts of the innocent.

A.D. 386 – 1871 7 witnesses

Patristic

before A.D. 750
386
A.D.
Cyril of Jerusalem Patristic
A.D. 313–386
“The heretics do this by coating over their poison pills of godless doctrines with the honey of the name of Christ.”
date
unknown
c. A.D. 400
“That "the harvest is great, but the workmen are few," this also is well-known and manifest. Let us, therefore, "ask of the Lord of the harvest" that He would send forth workmen into the harvest; [Matthew 9:37-38] such workmen as "shall skilfully dispense the word of truth;" workmen "who shall not be ashamed;" faithful workmen; workmen who shall be "the light of the world;" [Matthew 5:14] workmen who "work not for the food that perishes, but for that food which abides unto life eternal;" [John 6:27] workmen who shall be such as the apostles; workmen who imitate the Father, and the Son, and the Holy Spirit; who are concerned for the salvation of men; not "hireling" [John 10:12-13] workmen; not workmen to whom the fear of God and righteousness appear to be gain; not workmen who "serve their belly;" not workmen who "with fair speeches and pleasant words mislead the hearts of the innocent;" [Romans 16:18] not workmen who imitate the children of light, while they are not light but darkness — "men whose end is destruction;" [Philippians 3:9] not workmen who practise iniquity and wickedness and fraud; not "crafty workmen;" [2 Corinthians 11:13] not workmen "drunken" and "faithless;" nor workmen who traffic in Christ; not misleaders; not "lovers of money; not malevolent."”
Source
407
A.D.
John Chrysostom Patristic
A.D. 347–407
“Again an exhortation, and prayer after the exhortation. For after telling them to "mark them which cause divisions," and not to listen to them, he proceeds, "And the God of peace shall bruise Satan under your feet shortly:" and, "The grace of our Lord be with you." And notice how gently too he exhorts them: doing it not in the character of a counsellor, but that of a servant, and with much respect. For he calls them brethren, and supplicates them likewise. For, "I beseech you, brethren," (he says). Then he also puts them on the defensive by showing the deceitfulness of those who abused them. For as though they were not at once to be discerned, he says, "I beseech you to mark," that is, to be exceedingly particular about, and to get acquainted with, and to search out thoroughly-whom, pray? why, "those that cause divisions and offences, contrary to the doctrine which ye have learned." For this is, if anything the subversion of the Church, the being in divisions. This is the devil's weapon, this turneth all things upside-down. For so long as the body is joined into one, he has no power to get an entrance, but it is from division that the offence cometh. And whence is division? From opinions contrary to the teaching of the Apostles. And whence come opinions of this sort? From men's being slaves to the belly, and the other passions. For "such," he says, "serve not the Lord, but their own belly." And so there would be no offence, there would be no division, unless some opinion were thought of contrary to the doctrine of the Apostles. And this he here points out by saying, "contrary to the doctrine." And he does not say which we have taught, but "which ye have learned," so anticipating them, and showing that they were persuaded of and had heard them and received them. And what are we to do to those who make mischief in this way? He does not say have a meeting and come to blows, but "avoid them." For if it was from ignorance or error that they did this, one ought to set them right. But if they sin willingly, spring away from them. And in another place too he says this. For he says, "Withdraw from every brother that walketh disorderly" (2 Thess. iii. 6): and in speaking to Timothy about the coppersmith, he gives him the like advice, and says, "Of whom be thou ware also." (2 Tim. iv. 15.) Then also to lash those who dare to do such things, he mentions also the reason of their devising this division. "For they that are such," he says, "serve not our Lord Christ, but their own belly." And this he said too when he wrote to the Philippians, "Whose god is their belly." But here he appears to me to intimate those of the Jews, whom he ever uses particularly to find fault with as gluttonous. For in writing to Titus too, he said of them, "Evil beasts, slow bellies." And Christ also blames them on this head: "Ye devour widows' houses," He says. And the Prophets accuse them of things of the kind. For, "My beloved," He says, "hath waxen fat and gross, and hath kicked" (Deut. xxxii. 15). Wherefore also Moses exhorted them, and said, "When thou hast eaten and drunken and art full, remember the Lord thy God." And in the Gospels, they who say to Christ, "What sign showest thou unto us?" (John vi. 30) pass over everything else, and remember the manna. So do they everywhere appear to be possessed with this affection. How then comest thou not to be ashamed at having slaves of the belly for thy teachers, when thou art a brother of Christ? Now the ground of the error is this, but the mode of attack is again a different disorder, viz. flattery. For it is by "fair speeches," he says, "that they deceive the hearts of the simple." For their attention reaches only to words; but their meaning is not such, for it is full of fraud. And he does not say that they deceive you, but "the hearts of the simple."”
Source

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
“For your obedience is come abroad unto all men,.... That is, as the Arabic and Ethiopic versions render it, "the fame" and report of their obedience to the faith, to the doctrine of the Gospel, and the ministers of it, was spread everywhere, was well known to everyone, and spoken of with commendeth among all the churches in all nations: and this the apostle mentions as another reason why they should beware of false teachers, since it would be greatly to their reproach, should they, after all this, drop that form of doctrine which they had obeyed, desert the faithful ministers of the word, and follow these false teachers; should this be the case, they would be as notorious for their disobedience, as now for their obedience: and moreover, the apostle might hereby suggest, that whereas it was everywhere known how readily and at once they embraced the Gospel of Christ; this credulity and readiness to believe, which was their commendation, might have invited false teachers among them, who might hope and take encouragement from hence the more easily to gain upon them; and therefore they ought to be upon their watch and guard, and beware of them, and not believe every spirit: I am glad therefore on your behalf; that they had so cheerfully and readily embraced the Gospel, and from the heart obeyed that form of doctrine delivered to them; and that their praise for this was in all the churches of Christ, and had everywhere a good report on this account: but yet I would have you wise unto that which is good, and simple concerning evil; which is just the reverse of natural and unregenerate men, who are wise to do evil, but to do good they have no knowledge; some reference seems to be had to the words of Christ in Mat 10:16; the apostle's meaning is, that though he rejoiced at the heartiness and simplicity of their obedience, and the credit they obtained abroad on account of it, yet was he not without his fears and jealousies concerning them; and could not but greatly wish them more wisdom to understand the doctrines of the Gospel, to discern things that differ, and approve that which is the most excellent, and hold fast that which is good; and with all their harmlessness, innocence, and simplicity, prudently guard against all evil doctrines and principles, such as might unawares lead them into bad practices, dishonourable to religion, and uncomfortable to themselves.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“They - serve not our Lord Jesus - They profess to be apostles, but they are not apostles of Christ; they neither do his will, nor preach his doctrine; they serve their own belly - they hate intruded themselves into the Church of Christ that they might get a secular support; it is for worldly gain alone that they take up the profession of the ministry: they have no Divine credentials; they convert not the heathen nor the ungodly, for they have no Divine unction; but by good words and fair speeches (for they have no miraculous nor saving powers) deceive the hearts of the simple, perverting Christian converts, that they may get their property, and thus secure a maintenance for themselves. The Church of God has ever been troubled with such pretended pastors - men who Feed themselves, not the flock; men who are too proud to beg, and too lazy to work; who have neither grace nor gifts to plant the standard of the cross on the devil's territories, and by the power of Christ make inroads upon his kingdom, and spoil him of his subjects. On the contrary, by sowing the seeds of dissension, by means of doubtful disputations, and the propagation of scandals; by glaring and insinuating speeches, χρηστολογιας, for they affect elegance and good breeding, they rend Christian congregations, form a party for themselves, and thus live on the spoils of the Church of God. Should it be asked, Whom do you intend by this description? I answer: No soul, nor party, but such as the description suits. Irasceris.? - De Te fabula narratur. O, you are angry, are you? O, then, the cap fits you - put it on.”
Source
1871
A.D.
1871
“For they that are such serve not our Lord Jesus Christ--"our Lord Christ" appears to be the true reading. but their own belly--not in the grosset sense, but as "living for low ends of their own" (compare Phi 3:19). and by good words and fair speeches deceive the simple--the unwary, the unsuspecting. (See Pro 14:15).”
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.