In theology and biblical studies, the German phrase existentiale Interpretation was and still is closely associated with the New Testament interpretation of Rudolf Bultmann and in particular his debt to Martin Heidegger. More radical revisionists want a fuller account of human existence and our relationship to nature as well as society than Heidegger provided, calling at least for some expansion of Bultmann's model. Heidegger's phenomenological description of inauthentic and authentic human existence clarified that and so signalled the difference made by the non-objectifiable act of God in Christ actualised in the kerygma. Karl Barth saw a return to the anthropocentrism of nineteenth-century liberal theology. As early as 1930, Bultmann was having to answer the charge of imposing an alien system on Christian theology by explaining how he uses these categories. Depending exclusively on the word of God proclaimed requires the understanding that faith seeks.