The essay examines the role of Christianity in premodern European capitalism, with regard to the city of Florence. It traces the formation of the historical construct and the influence of Werner Sombart's Der moderne Kapitalismus, a work much neglected nowadays in the Anglophone academy. The article seeks to historicize and contextualize faith and economy, to stress their fundamentally intertwined nature and more specifically how notions of “negotiation” and diriturra (moral Christian rectitude) connect the seemingly antagonistic sides, and connect also Florentine finance and business history, which are too often studied independently. It argues that Christian rectitude and service to the church (a noncynical quid pro quo) were conjoined with a calculated, reasoned profit motive--evident especially among papal bankers, a key sector of the Florentine economy.