The significance of E. Bonhoeffer's theology for the modern and postmodern society can be firstly seen in his dissertation Sanctorum Communio. Although the postmodern philosophy tries to decentralize the subject elevated by the modern, for Bonhoeffer it is still trapped in the enclosed ego and can no real community as well as individual be established. Bonhoeffer criticizes the two opposite understandings of person, Aristotelian and German Idealist, Stoican and Epicurean, for not taking the otherness of the other serious enough. The former considers that one can be an individual only in the community whereas the latter takes that every person is self sufficient. Bonhoeffer asserts the principle of barrier and the priority of the other when he attempts to establish both the difference and inseparateness of I-Thou. He further grounds these understandings on the duality of God and humanity, the structured openness and closedness of humanity, and the most fundamental 'Christ existing as community'. However, due to his dialogical grammar of Christology the establishment of individual and community is at stake.