Take a man's garment when he has put up security for a stranger,
and hold it in pledge when he puts up security for an adulteress.
Some years ago a former student of mine did work for me over a series of years. This young man, I believed, was so trustworthy that at one time I said to my wife that I could trust him with all my resources. I knew that he would never steal from me or misuse anything that I owned. To this day, I would still trust this man.
Proverbs 27:13 reminds us that not all people are as trustworthy as this former student. The text reveals that some will (1) take advantage of us by asking for further loans but with no intent to repay (verse 13a), and (2) take advantage of women for selfish purposes. Both of these decisions are very unwise. The end result that the author is trying to convey is that unless the trend is stopped, poverty will set in.
This idea was mentioned in Proverbs 20:16, so the repetition of it should cause us to take special of the warning. Beware of those who would seek to use our financial resources in a dishonest manner. We may never see our resources returned. And beware of those who mistreat women by posing to be something they are not. Some women can be easily enticed, thinking that a promise will be fulfilled. This does not always end the way one would want to believe, and both the man and the woman will follow roads that are very unwise.
The text is not opposed to the idea of “lending to a brother in need” nor appropriately befriending someone of the opposite sex. The warning is that there are those in this fallen world who take advantage of others’ resources as well as taking advantage of other people. Let us be wise in following this wisdom.