This chapter presents the second part of The Sickness unto Death, “Despair as Sin,” as the Aufhebung or recontextualizing of the first part in which the concept of sin does not function.  Both parts portray the self as existing “before God,” but that concept is so indeterminate in the first part that it fits just as well with Spinoza’s or Hegel’s “God” as with the biblical God Kierkegaard has in mind. Sin, along with essentially related concepts such as atonement and forgiveness, is the decisive category that distinguishes biblical religion (Jewish or Christian) from “theologies whose foundations are scientific naturalism (Spinoza) or socio-historical pantheism (Hegel). The latter are “Socratic” in that they rely on some version of recollection theory (Reason), while the former rests on a concept of revelation that is not reducible to a truth already within us. Reason turns out to be as sectarian as the faith that rests on some extra-rational revelation. While both parts of the text are psychological/phenomenological, neither permits the reduction of despair to depression.