It is better that you should not vow than that you should vow and not pay. Ecclesiastes 5:5
This verse could be seen to apply to our current times quite well. With our current housing and foreclosure crunch people have been taking out loans left and right, making vows to repay, and then not repaying. Why? They may have felt pressure to move into a bigger house, or to drive a better car. Whatever their reasons, they made a vow, but ended up not following through.
This verse speaks to the wisdom of not making a vow (taking out a loan or going into debt) that you may not be able to follow through on. Better yet, start doing a budget, save up your money and pay cash for the things you buy!
For which of you, intending to build a tower, does not sit down first and count the cost, whether he may have enough to finish it. Luke 14:28-30