Written in 1907 by Charles Augustus Briggs, an American professor of theology, the main themes of this article are papal authority, Protestantism and modern life. Throughout the work, Briggs defends the authority of the papacy and its superiority over other churches and emphasizes that Christian unity can only be achieved under the papal authority. However, Briggs also justifies the Protestant movement's attitude towards the Roman Catholic Church and states that it was the corruption in the Papacy that pushed both Luther and his followers to this point. It is surprising that on the one hand he defends papal authority and on the other hand he supports the Protestant movement by saying that the Roman Church has become corrupt. However, the Episcopal Church, to which he belonged, enabled Briggs to bring together these two seemingly contradictory ideas. What lies behind the idea of the importance of modern as one of the main outlines of this paper is that Briggs is an American. Emphasizing modern states and the system of government of the United States of America, Briggs mentions the benefits of the principle of separation of powers in modern states and suggests that the Papacy should also adopt such a form of government. Briggs argues that Christian unity can only be established by bringing together Catholic teachings, the Protestant movement and modernity, and thinks that if these three elements are united under the roof of the Papacy, the ideal Papacy will emerge.