The Concept of Sin and Human Existence in Christianity on Kierkegaard's The Sickness unto Death-and Bultmann's Development

The Sickness unto Death and The Concept of Anxiety were written by Kierkegaard's pseudonymous authorship. Both of them discuss about the concept of sin in Christianity and from the perspective of psychological phenomena in human existence reinterpret the harmatology. That is Kierkegaards writing character, he reflected Christianity and discussed with theological tradition but at the same time he rather expected, that his theses could bring clear light to the readers, in order that they could see the exact encounter between Christianity and their existence. In this text I should first illustrate the concept of sin in The Sickness unto Death, which is developed through analyzing the phenomena of human existence. Then, I should discuss Bultmann's issues about the will/decision and the human existence, which are unfolded on the base of Kierkegaard's perspective. At the conclusion I should also talk with some researches of cognitive science and explain that the approach of Kierkegaard's harmatology still has its appropriateness for the current theology.