John Calvin Commentary Romans 16:17

"Now I beseech you, brethren, mark them that are causing the divisions and occasions of stumbling, contrary to the doctrine which ye learned: and turn away from them." — Romans 16:17 (ASV)

And I beseech you, etc. He now adds an exhortation, by which all Churches often need to be stirred up. For the ministers of Satan are always ready to take the opportunity to disturb the kingdom of Christ. They attempt to make disturbances in two ways: they either sow discord, by which people's minds are drawn away from the unity of truth, or they cause offenses, by which people are alienated from the love of the gospel.

The first evil occurs when the truth of God is mixed with new dogmas devised by people, and the second takes place when, through various schemes, the gospel is made hateful and contemptible. He therefore commands that all who do either of these two things should be watched, so that they do not deceive and trap the unwary. They should also be shunned, because they are harmful.

It was not without reason that he required this vigilance from the faithful. For it often happens through our neglect or lack of care that such wicked people do great harm to the Church before they are resisted. They also creep in with astonishing subtlety to do mischief, unless they are carefully watched.

But note that he is speaking of those who had been taught the pure truth of God. It is indeed an impious and sacrilegious attempt to divide those who agree in the truth of Christ. However, it is a shameful sophistry to defend, under the pretext of peace and unity, a union in lies and impious doctrines.

Therefore, there is no ground for the Papists to seek support from this passage to stir up ill-will against us. For we do not attack and tear apart the gospel of Christ, but rather the falsehoods of the devil, by which it has, until now, been obscured. Indeed, Paul clearly shows that he did not condemn all kinds of discords, but only those that destroyed agreement in the orthodox faith. The force of the passage is in the words, which you have learned; for it was the duty of the Romans, before they were correctly taught, to depart from the habits of their fathers and the institutions of their ancestors.