Romans 16:19

For your obedience is come abroad unto all men: q.d. As for you, your ready embracing of the gospel, and conformity thereunto, is generally taken notice of by all that mind such things: see the like, Romans 1:8 1 Thessalonians 1:8. I am glad therefore on your behalf; I rejoice to hear of your soundness and teachablehess; I do not therefore speak this to accuse, but to caution you. But yet I would have you wise unto that which is good, and simple concerning evil: q.d. Take heed that you be not cheated by seducers, that thcy do not abuse your tractableness to draw you into errors. He exhorts them to join prudence with simplicity; to be so harmless and simple as not to invent false doctrine, and yet to be so wise and skilful as to be able to discern truth from falsehood; to be so innocent as not to deceive, and so prudent as not to be deceived: see Matthew 10:16. He prays for the Philippians, that they may have this discretion, Philippians 1:9,10, and exhorts the Thessalonians thereunto, 1 Thessalonians 5:21.