In my paper I set the existential interpretation of Dostoevsky’s Notes from the Underground proposed by Lev Shestov against the religious and psychological interpretations of this novel in order to excavate a vital problem in Dostoevsky, which is the inversion of hierarchy in pairs of oppositional categories such as normality-pathology, happiness-unhappiness, harmony- dissonance, omnitude-lack, certainty-uncertainty, joy-despair, faith-doubt. Following Shestov I argue that Dostoevsky embraces those categories that are traditionally mistrusted and negatively valorized and by so doing he rehabilitates the “underground”, accursed and unhappy existence at the expense of regular, “normal” life, easily founding spiritual certainty and every day satisfaction. Such an un-problematic life Dostoevsky’s man from the underground regards as a false, smug and eventually – “dead”. In further part of my study I focus on the religious aspect of Shestov’s later philosophy and try to prove that the perspective of faith gradually introduced to his reading of Dostoevsky in no way cancels Shestov’s early philosophy of the underground, despair and tragedy. On the contrary: if faith “obtained” is likely to become yet another mask of “evidence” and “certainty” and in this way might put stop to existential doubts and spiritual dissatisfaction, then neither Dostoevsky, nor Shestov himself, can easily trust it. In this situation despair and tragedy cannot but hold in Dostoevsky’s and Shestov’s thought and the circle of searching and suffering must remain vicious. I demonstrate the consistency in Shestov’s philosophical thought on Dostoevsky and its constant adequacy for understanding one of the crucial existential dilemmas in the works of the Russian writer.