This paper explores the reasons for the intensive use of deception in comedias of Tirso, focusing on theology and philosophy. The goal of this discussion is to epistemologically pursue the origins behind Tirso’s active application of literary device, deception. Spain chose realism, which was revived in the Middle Ages in the ideas that drove the Counter-Reformation. Realism suited the universality of papal and imperial sovereignty. Specifically, it was an idea supporting the centralization of power in the Empire and the Roman Catholic Church. However, as is well known, realism lost its utility value with the discovery of Copernicus. As a result, in Spain, the will to revive realism led by the government and the Roman Catholic Church and the will to reject realism, which was judged to be erroneous, were to refute each other. Capturing the meaning hidden under laughter delighted the enjoyment class, and the frequent use of deception can be seen as a result of the reflection of the enjoyment class’ desire for it. In addition, the fact that it did not disturb the social order was another real pleasure of fraud. Tirso de Molina, who unflinchingly aesthetically exposed it in a bleak age without antagonizing it, show us that entertainment and art can coexist.