This paper is an attempt to trace the discourses on conscience and its background in Jacobi’s Woldemar Part I as a starting point for understanding the meaning and significance of conscience in the history of Western ethical thought from the late 18th century to the early 19th century. In the first part of Woldemar, Woldemar as a main character in the book talks about “conscience” as the source of morality, and this paper points out that the features found in this “conscience”, such as autonomy, authority, sentiment, and mediation between general principles and particular actions, are influenced by Joseph Butler, Rousseau, virtue ethics, and casuistry. On the other hand, there is another view of conscience presented in Woldemar Part I which is in opposition to the former one, and its features are reminiscent of Lutheranism and Kant’s view of conscience. Through these contrasts, Woldemar highlights the various aspects of the discourses on conscience, their relationships, and their conflicts in the beginning of modern times. This gives us a new perspective on the developments in the latter half of Woldemar , as well as on the interpretations and background research about Hegel’s theory of conscience, especially his theory of reconciliation, which was influenced by the Woldemar.