This book seeks to demonstrate that the suffering of God has an «ontological status» in Luther's Theologia Crucis. The discussion concentrates on three constituents of Luther's theology - Christology, soteriology, and Trinity - to see how each of them establishes the assertion that God suffers. Does God suffer within himself or does God suffer only in the humanity of Jesus Christ or does only the God-Man Jesus Christ suffer? Dennis Ngien places Luther within the context of the medieval Church, the early Church's discussion of the suffering of God and the modern discussions of the essential Apathy. Luther accepts the Old Church's Theopaschitism, but he rejects Patripassianism, a heresy of the Old Church. This study breaks new ground by taking Luther a step further, arguing that only a trinitarian theology of the cross is genuine Christian theology, and that the suffering of Christ touches the immanent Trinity as well as the economic Trinity. Ngien also engages in useful discussions with other scholars including Paul Althaus, Walter von Loewenich, Ian Siggins, Marc Lienhard, Eberhard Jüngel, Jürgen Moltmann, and Alister McGrath.