Emil Cioran, a French thinker of Romanian origin, his thought is often considered to be too difficult to classify and to have seemingly negative meaning of tiredness, boredom, melancholy, incompleteness and defeat. In fact, all of these notions are connected to ”acedia” which will be analyzed in this article. Firstly we will be interested in the Romanian period of Cioran's life, marked by his sympathizing with the extreme Right and his anti-Semitic comments. The second part of this study will show the consequences of this moral and intellectual mistake: Cioran's long-lasting remorse and its influence on his work, ”Cahiers”.