Short answers, pulled from the story.
Luis de Molina (the 29th of September 1535 - the 12th of October 1600) was a Spanish Jesuit priest, jurist, economist, and theologian. He is best known for developing Molinism, a theory reconciling divine omniscience with human free will, and for his contributions to early economic theory within the School of Salamanca.
Molinism is the theological position, developed by Luis de Molina, that God knows what any free creature would choose in any possible circumstances through scientia media, or "middle knowledge." This foreknowledge allows God to arrange creation and issue predestinating decrees without eliminating human freedom. The phrase "middle knowledge" was Molina's own coinage.
Dominican theologian Domingo Báñez denounced Molina to the Spanish Inquisition after Molina published the Concordia in 1588, which proposed a theory of grace and free will that opposed both Thomist and Augustinian traditions. Pope Clement VIII ultimately intervened in 1598 by appointing the Congregatio de Auxiliis to adjudicate the dispute.
Molina argued that just price is not determined by utility. In De iure et iustitia, he stated that the just price of a pearl used only for decoration is higher than the just price of grain, bread, or horses, even though those goods are more useful. He also articulated an early version of the quantity theory of money, writing that the more abundant money is in one place, the less its value.
The Congregatio de Auxiliis was an assembly of theologians convened in 1598 by Pope Clement VIII to judge whether Molinism conformed to Catholic doctrine. After many sessions it failed to reach a verdict; Pope Paul V suspended its meetings in 1607 and in 1611 prohibited further public discussion of efficacious grace altogether.
Molina extended a theory of price inflation first developed by Juan de Medina and Martin de Azpilcueta in Salamanca, arguing that greater abundance of money in a place reduces its purchasing power. His writings on voluntary exchange, property rights, and just price are considered precursors to Austrian economic theory and modern libertarian thought.