Iron Shapens Iron

When I would be confronting someone, people would say (iron sharpens iron). What ever that would mean? Then I ran across this verse and it was not as bad as I thought.
[Job 7:17] Iron sharpeneth iron; so a man sharpeneth the countenance of his friend.
[Iron - As hard iron, steel, will bring a knife to a better edge when it is properly sharpen against it: so one friend may be the means of exciting another to reflect, dive deeply into, and illustrate a subject, without which whetting or excitement, this had never taken place. That is, conversation promotes intelligence, which the face exhibits.
"But let me sharpen others, as the hone gives edge to razors, though itself have none."
The countenance - The company or conversation of one’s friend.
This intimates both the pleasure and the advantage of conversation. One person is nobody; nor will poring upon a book in a corner accomplish a person as the reading and studying of men’s will. Wise and profitable discourse sharpens one's wits; and those that have ever so much knowledge may by conference have something added to them. It sharpens one's looks, and, by cheering the spirits, puts a briskness and liveliness into the countenance, and gives a person such an air as shows he or she is pleased with themselves and makes them pleasing to those about them. Good people's graces are sharpened by converse with those that are good, and bad people's lusts and passions are sharpened by converse with those that are bad, as iron is sharpened by its like, especially by the file. Pleople are filed, made smooth, and bright, and fit for business (who were rough, and dull, and inactive), by conversation. This is designed:
1. To recommend to us this expedient for sharpening ourselves, but with a caution to take heed whom we choose to converse with, because the influence upon us is so great either for the better or for the worse.
2. To direct us what we must have in our eye in conversation, namely to improve both others and ourselves, not to pass away time or teasing one another, but to provoke one another to love and to good works and so to make one another wiser and better.]