As I understand it, the axiom that unreceived act is unlimited refers to the claim that one aspect of what it means for God to be infinite is that he exists as pure actuality lacking any potentiality. Therefore, He needs nothing to actualize His potential.
I’ve never heard the phrase “unlimited character of the free market” before so I’m unsure what it means. By it clearly cannot mean that the free market is pure actuality since the free market is merely part of the nexus of voluntary interactions among human beings.
Economists sometimes refer to the universal character of economic laws, but this refers to the conceptual meaning of human action and not actions themselves.