I am a PhD candidate at the Faculty of Religion and Theology, Vrije Universiteit Amsterdam, working on the Dutch historian of science Reijer Hooykaas (1906-1994). I reflect on the meaning of his scholarly activities for the field of science-and-religion as well as the historiography of science more broadly. Specifically Hooykaas’ research on the Reformation and science as well as 19th century geology provides me with ample material to study his methods and motivations.