Money is energy and is valued by the work (Effort Energy). The Money (currency) when printed in paper is equated to Gold, a  commodity that cannot be grown, but is fixed in resources.

In primitive days with barter system, the exchange is made on commodities that are grown and so the reference standard value is not fixed.

Currency when printed without equalting to a Gold standard has no value. This is the reason why any government does not print currency to remove poverty.

So wealth is a reflection of one's Energy of action (Karma). karma is from a root word "Krr" which means action. The "Curr" in currency also has the sound of Krr of karma to denote, it is a symbol of the effort energy.

In Ancient Bhaarath, all actions were equated to currency (coins) which was printed after equating to Gold. Gold was the "Gold" standard for a tangible exchange form of an in-tangible form of effort-Energy. So the kings always set aside an equavalent Gold before printing money. Now this Gold (tangible form of resource) was equal to the Cosmic Energy (God). Hence this Gold that was equated was kept in a temple and worshipped as God, because it represented the Karmic Energy.

This is the secret behind finding Gold in all Indian temples, especially the recently found one in Padmanabha Swamy Temple of Thiruvananthapuram or Trivandrum.

This karmic transfer of energy between the people on the basis of money was based on another secret discovered by Rishi's the seers of "intangible" cause for life. They equated to the Gold standard of "Self-awareness", which circulated brith after re-birth for any particualr individual. This Self-Awareness Energy (SAL ENergy)  is also due to work called sacrifice (Yagnya in Sansrit). How currency in a person reflects the individual's energy through work-effort, the luck in one's life is based on the SAL Energy of an individual.

Reference : Universal Self Pattern (2014- publication).