A model for us all

Parkinson's second law is that "Expenditure rises to match income".
This is a trueism of modern affluent Western society.
Or is it? Maybe it should be "Expenditure rises to match income plus how much the bank will lend you!"
But, Jesus said "You cannot serve both God and money" and so Christians must be different.

I was challenged by a post written by John Piper about the example of John Wesley. Throughout his life Wesley kept his annual expenditure at the same level (roughly 30 pounds) as when he was younger, in spite of the fact that his income sometimes was as high as 40+ times that!