It is an apparent danger in the existence of the modern man that abstraction is substituted for reality. The truth of the uniqueness of each man and the various situations of life where one cannot but make a personal choice and decision, compel man the need to authenticate his being. It is then pertinent at this time, when there is not only a loss of personal identity but more still a total flaw of existence in our modern society, to pinpoint what authentic life should be. Hence, a Danish philosopher Søren Kierkegaard has done a masterly work of authenticating one's existence, becoming an individual instead of being swallowed up in the appraisal of untrue crowd. Precisely, the researcher will apply in this work the philosophical method of critical reflection of Kierkegaardian three spheres of human existence to arrive at the best manner of approach to examine one's life as to live an authentic existence.