Chapter 3 explains that sin is not a "negation" but a "position." That is to say, sin is not merely the absence of virtue, but rather a distinct state of being, a condition that human beings willfully take on. Theologians who try to understand sin and other religious concepts in rational terms are mistaken. The essence of Christianity is that God has revealed to human beings that they are living in sin and that faith is the only way to overcome sin. Modern people tend to try to understand everything scientifically. We are in need of a modern Socrates to demonstrate to us how little we really understand--or even can understand--about fundamental concepts like sin and faith.
The Appendix begins with an expression of concern that the account of sin in Chapter 3 may have led the reader to the conclusion that sin is a rare quality. This is not a correct interpretation. Just as there are varying degrees of despair, so are there varying degrees of sin, ranging from a general indifference to religious matters to an outright rebellion against Christ's teachings. Indifference may not seem to be sin in the fullest sense. Nevertheless, it is sin insofar as it involves a failure to accept Christian truth. Kierkegaard criticizes the Church leaders of his day for encouraging people to think that they can be true Christians while living lives of indifference. Church leaders should instead emphasize the difficulty and paradoxicalness of Christ's teachings.
Kierkegaard's argument that sin is a "position" recalls Kierkegaard's earlier suggestion (see I.A.b., for instance) that people are responsible for their condition of sinfulness. For Kierkegaard, sin is the condition of rejecting Christ's teaching and failing to pursue faith; it is the condition of remaining in despair even after Christ has shown us how despair may be overcome. Kierkegaard's point is that this condition involves much more than simply failing to live virtuously. It involves a willful refusal to accept Christian truth.
In the course of this discussion, Kierkegaard emphasizes, once again, that the scientific approach to religion is misguided; that Christian teachings are a paradox that insults our rationality; and that modern times are in need of a Socrates (implying perhaps that Kierkegaard is trying to serve as just such a figure--see the discussion of Socrates in the commentary to Chapter 2).
The Appendix clarifies Kierkegaard's understanding of sin. It stresses that, to Kierkegaard's mind, anyone who has been exposed to Christ's teachings and fails to pursue faith is in sin. People who lead petty lives, indifferent to religious issues, may be uninteresting, but they are in sin nonetheless.
Kierkegaard's criticism of church leaders helps to clarify his views on organized religion. For Kierkegaard, religion should be an obsessive, consuming concern. It should also be intensely private, involving internal reflection rather than discussion and ritual. An organized church that makes Christianity a mundane affair or casual commitment is therefore not a true church to Kierkegaard's mind. (See also Part I.C.a.)