This article purports to make an interpretative study of the first book of Pufendorfs On the Duty of Man and Citizen According to Natural Law. It has the following two purposes. On the one hand it aims to provide an elucidating full account of what Pufendorf understands under the main themes of natural religion and man`s moral duties toward God. For this purpose it deals with such sub-themes as God`s existence and essence, reason and faith, knowledge and revelation, the argument for the existence of God from the outside in contrast with that from the inside, the analogical use of religious language, deism-oriented theism in distinction from atheism, moral argument for the existence of God, religion for morality.
On the other hand taking the context of the history of religious philosophy and moral philosophy into consideration the author intends to make clear Pufendorfs philosophical place and significance in it. For this purpose he attempts to carry out an excavating inquiry so that he may bring out the dual histories of both reception and influence that can be said to lie implicit and hidden in Pufendorfs conception of natural religion not only by focusing on Pufendorf but also by comparing Pufendorf (even if in an oversimplified way) with such philosophers as Aristotle, Augustinus, Anselm, Aquinas, Descartes, Leibniz, and Kant with either identification or distinction in view.