Since much is known of Desiderius Erasmus' early education, religious affiliations, and personal piety, this thesis suggests that scholars can examine the theologian's life to glean information on Hieronymus Bosch's own values and influences. Both men lived in 's-Hertogenbosch for at least a portion of their lives, belonged to lay religious groups that adhered to analogous ideals, and shared a mutual love for didacticism and the popular literature of the time. They also worked during the same turbulent period of religious unrest, accounting for the undeniable parallels that exist between Erasmus' writings and the artist's visual imagery.

This thesis analyzes the iconography and patronage of the Haywain Triptych, the Garden of Earthly Delights, and some of Bosch's smaller paintings while suggesting that an examination of Erasmus sheds light on the artist's puzzling practice. This thesis also strives to establish a more appropriate methodological framework for future Bosch studies.