The proverb expresses the gain of mutual counsel as found in clear, well-defined thoughts. Two minds, thus acting on each other, become more acute. This is better than to see in “sharpening” the idea of provoking, and the point of the maxim in the fact that the quarrels of those who have been friends are bitter in proportion to their previous intimacy.
Related Commentaries of Proverbs 27:17
Proverbs 27:17
17 Iron sharpeneth iron; so a man sharpeneth the countenance of his friend.