Milton Friedman is a world famous economist. He said that the way to know someone's value system, what is REALLY important to them is NOT what he says but HOW HE SPENDS HIS MONEY.
I have found very often in life that people will say all the right things until it comes to writing a check. But the deepest beliefs of a person are revealed in his checkbook...
Yesterday I went to a הכנסת ספר תורה. When someone [not a rich man by any means] drops 40-50k on a sefer Torah [when Klal Yisrael has already has countless sifrei Torah] that says something. When someone spends hundreds of dollars on arba minim that says something. When someone gives a significant portion of his income to tzedaka that says something.
The inverse is also true - וד"ל.