God's word illumines the darkness of society. Dutch politician and historian Groen van Prinsterer's Unbelief and Revolution is a foundational work addressing the inherent tension between the church and secular society. Writing at the onset of modernity in Western culture, Groen saw with amazing clarity the dire implications of abandoning God's created order for human life in society. Groen's work served as an inspiration for many contemporary theologians, and he had a profound impact on Abraham Kuyper's famous public theology. In Challenging the Spirit of Modernity, Harry Van Dyke places this seminal work into historical context, revealing how this vital contribution still speaks into the fractured relationship between religion and society. A deeper understanding of the roots of modern secularism and Groen's strong, faithful response to it gives us a better grasp of the same conflict today.