And these words, which I command thee this day, shall be upon thy heart.  And you shall teach them to your sons and speak of them when you sit in your house, and when you walk on the way, and when you lie down and when you rise up. Deuteronomy 6:7 Train up a child in...

I am not sure how I learned the simple rule of "Spending less than you earn."  But I learned it. I suspect it was a lesson taught by example.  But, I don't know.   I know many people that as adults have completely different spending habits than their parents....