Proverbs 22:26-27 "Be not thou one of them that strike hands, or of them that are sureties for debts. If thou hast nothing to pay, why should he take away thy bed from under thee?"

“Striking hands” is not a warning against fighting but rather in context of the traditional handshake of sealing a deal. Be careful with putting your good name on the line for another. The warning is against loaning money, or rather being a co-signer. Especially for someone who is a high risk of not being able to repay. In such situations, one ought to consider if they can afford the loss, and if so, be prepared to do so. In certain situations, a financial gift ought to be considered rather than a loan.

From this Scripture we are also shown how that there ought to be mercy and forgiveness of those whom cannot repay. One ought not to be so harsh as to take the bed out from under the debtor. Such behavior would have nothing to do with recouping loss and everything to do with revenge and expressing anger. We should be grateful our Lord is not so! (See Luke 7:40-47). Those who have obtained forgiveness and mercy ought to extend it (See Matthew 18:23-35).

Several years ago I use to work for a used car dealer. Among my many duties, I was sometimes required to help repossess cars. On one such occasion, we went looking for a guy who had been difficult to catch up to. After some time of making phone calls and visiting some of his family and friends, we learned he was at a local lake fishing. We explored the various fishing sites accessible to vehicles and soon found the car we were looking for. Without looking to notify the guy of the situation, my boss took the car. We had left the guy to not only discover that the car was gone but that he was also stranded. I later learned that the guy had only one payment left that he owed on the car. Perhaps there was more going on than I knew, but I felt it was a rotten thing to do. 
 
We would be wise to remember that the Lord is an observer of the behavior of both the debtor and the lender. May both be wise, honest and merciful in their dealings with one another.