Romans 16:18

Withdraw from them, he says. If they were doing this out of ignorance or error, they would need to be corrected. But since they sin deliberately, flee from them. He hints at the Jews, whom he customarily reproaches as gluttons; for such is their entire …

By good words - Concerning themselves, making great promises. And fair speeches - Concerning you, praising and flattering you. The harmless - Who, doing no ill themselves, are not upon their guard against them that do.

Now observe his description of them, in two things:-- (1.) The master they serve: not our Lord Jesus Christ. Though they call themselves Christians, they do not serve Christ; do not aim at his glory, promote his interest, nor do his will, whatever they pretend. How many are there who call Christ Master and Lord, that are far from serving him!

For they that are such serve not our Lord Jesus Christ,....

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.

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 Php 3:19). and by good words and fair speeches deceive the simple--the unwary, the unsuspecting.

Serve not - Obey not. Though they are professedly, yet they are not his real friends and followers. But their own belly - Their own “lusts;” their own private interests; they do this to obtain support. The authors of parties and divisions, in church and state, have this usually in view. It is for the indulgence of some earthly appetite; to obtain function or property; or to gratify the love of dominion. And by good words - Mild, fair, plausible speeches; with an appearance of great sincerity, and regard for the truth; compare Col 2:4; 2Pe 3:3. People who cause divisions commonly make great pretensions to peculiar love of truth and orthodoxy; and put on the appearance of great sincerity, sanctity, and humility. And fair speeches - Greek εὐλογίας eulogias, eulogy, praise, flattery. This is another very common art. “Flattery” is one of the most powerful means of forming parties in the church; and “a little special attention,” or promise of an office, or commendation for talents or acquirements, will secure “many” to the purposes of party whom no regard for truth or orthodoxy could influence a moment. Deceive the hearts of the simple - The minds of the unsuspecting, or those who are without guile τῶν ἀκάκων tōn akakōn. The apostle means to designate those who are simple-hearted, without any disposition to deceive others themselves, and of course without any suspicions of the “designs” of others. He has thus drawn the art of making parties with the hand of a master. First, there are smooth, plausible pretences, as of great love for truth. Then, an artful mingling of attentions and flatteries; and all this practiced on the minds of the unsuspecting, drawing their “hearts” and “affections” toward themselves. Happy would it have been if the art had been confined to his own times.