Tzav: regulations 

It is not surprising that a parsha named tzav, "command". should be about regulations Most of the parsha deals with rules regarding various offerings  on the alter.  The rules restrict the nature of the service, the place of the service and the provider of the service.  It also includes rules about  the compensation (payment) for the provider.  This payment  includes the hides, pieces of meat,and baked goods. 

The Cohen is set up as Gd's representative.  Such a representative is needed because economic interactions with Gd are hard to understand.  The Provider of Everything does not need our gift, but the surrogate can use it, eat it, wear it.  The loss implicit in sacrifice needs to happen for the expiation to take hold (Mishna Babba Kamma 9:12). 

This is an example of the economic consequences of licensure.  There is profit to those who are permitted to perform a service to the exclusion of the unlicensed  The economic consequence of regulation often dominates over the quality control that is invoked to justify the regulation. 

May we all be spared the heartbreak of Pigul.