Throughout the history of theology, the doctrine of God has been approached in different ways that reflect the specific ecclesiastical, cultural, and philosophical contexts of the time. This raises the hermeneutical question of how the method of theology affects the belief content expressed by it. Or, the other way around, can certain substantial insights be detected that have a regulative function for the method of the doctrine of God? This two-way connection of method and contents is investigated in three important blocks of Protestant, Reformed theology. The first part joins the revived interest in Reformed scholastic theology, and attempts to discover the inner dynamics of this allegedly dry and rigid, Aristotelian theology. The second parts treats Karl Barth’s doctrine of God as – at first sight – a contrast model for scholasticism, and interprets this doctrine in the framework of Barth’s theological method. In the third part, a first comprehensive description and analysis of the efforts of the so-called Utrecht School is provided. The final chapter draws some lines for developing a Reformed doctrine of God in the 21st century.