Do not be a man who strikes hands in pledge or puts up security for debts; if you lack the means to pay, your very bed will be snatched from under you.
He who puts up security for another will surely suffer, but whoever refuses to strike hands in pledge is safe.
A man lacking in judgment strikes hands in pledge and puts up security for his neighbor.
Take the garment of one who puts up security for a stranger; hold it in pledge if he does it for a wayward woman.
--Proverbs 20:16 on the wisdom of demanding collateral when lending to AIG