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 ( Matthew 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.