When he heard the voice that ordered him to sacrifice his son, was Abraham deluded? When is faith merely a form of self-deception? The existential challenge of attaining and preserving faith is as difficult today as ever before and perhaps even more so in a scientifically, technologically oriented culture. Faith can turn into inauthenticity as easily today as in Kierkegaard's era. This book presents Kierkegaard's illuminating responses to the existentially haunting questions of faith and authenticity.