Schlesinger's pastoral work raised questions about the relationship between the church's life of worship (liturgy) and its engagement with the world around it (mission), which in turn drove him to pursue doctoral studies at Marquette University. This, in turn, ignited his love for teaching, especially at the undergraduate level. Dr. Schlesinger specializes in twentieth-century Catholic thought with a particular focus on developments in liturgical and sacramental theology and their impact on the Christian church. His current research itinerary explores the centrality of a theology of sacrifice for understanding Christian existence and the theme of salvation in the theology of Henri de Lubac.