The preliminary purpose of this research is to stay away from the dichotomy approach of evaluating Hwang, Sa-young(皇嗣永, Alexius) as an expatriate or a martyr. Instead it will observe and analyze HSY as one of the first 'modern men'. Around 1790, HSY considered Catholicism to be 'a medicine to save the world'{救世之良藥} and accepted it as an alternative to Confucianism, Chos?n's ruling ideology. Thus he gave up to take the civil examination(科擧), and instead became an ardent follower of Catholicism. When the Catholic persecution of 1801(辛酉迫害) occurred, HSY escaped to Baeron(배론) which is located in Jech?n, Kangwon Province. There he wrote Silk Letter(帛書) in hopes of salvaging the Catholic church throughout Chosen. When he was arrested, the Silk Letter was also found, and he was executed for crimes of treason against his country. Ever since the 17th century, Neo-Confucianism(性理學) gradually became more dogmatic. Chos?n society lost its social pliability. Thus the social order deteriorated and the traditional ruling system centered around the yangban(兩班) began to falter. In this kind of situation, a number of the scholar started searching for new ideology for social reform, and Catholicism was not an exception. Therefore, it were the Namin(南人) political faction that gave interest to Catholicism in order to improve Confucianism, and Catholic Churches were independently founded in Chos?n. However when the issue of a religious service for an ancestor came about, many yangban who previously accepted Catholicism, left their new found religion. In contrast, some of the people like Jeong Yank-jong(丁若鍾) and Yoon Ji-chung(尹持忠) forsook Confucianism and exclusively became Catholics. HSY was most likely influenced by people like them. When Catholicism was persecuted and struck down, it probably stimulated the already devour HSY to be more anti-Confucianism. For his faith, HSY denied the foundational concepts and values of Confucianism. Accordingly, the yangban-centered society which was built on Confucian ideals were also objects of denial. This was a task of great burden that one man could have hardly withstood. Furthermore when the Catholic persecution of 1801(辛酉迫害) happened, HSY wrote an impassioned and solution-seeking document named Silk Letter. HSY and his Silk Letter was decried upon, both in his epoch and also in later times. This is because Silk Letter contained two controversial suppositions. Primarily, that Ch?ng(淸) should supervise Chos?n for ensurance of the freedom of Faith. Furthermore, that the West sends armed fleets for militaristic measures. In a nationalistic aspect, he was against his own country and his people. However, it is undeniable that he is a religious martyr in his own right. It is unwise to dichotomy approach HSY as either an expatriate or a martyr. This is because he is not one or the other, but both simultaneously. The discussion regarding his request for militaristic aid is not a crucial one. Instead, more focus should be given on the fact that HSY viewed the Chos?n dynasty and its social structure as objects of ultimate eradication. The society of Chos?n and its people were governed by the Noron(老論) political faction. HSY sought to convert the people to Catholicism, thereby formulating an ideal society. Unfortunately, his dreams never saw the light. Nonetheless, the shockwave that HSY thrusted upon the society of Chos?n deteriorated it and opened the door into the modern world. HSY called himself a 'Christian' instead of a 'Confucian man of Chos?n'. This is because he wanted to forsake the Confucian cosmos and ingress into the Christian world. Hence, when he referred to asking the West for militaristic aid, he was only articulating upon a particular method that might be utilized to construct his ideal society. Notions and actions such as these that HSY held firm in his mind deserve to be called revolutionary. In HSY's time, history was flowing and paradigms were changing to the modern era. One could say that HSY ransacked for a key to open the stiff padlock of change. Obviously, his actions were criticized as treason by the ruling class of his contemporary society. Despite his demise, the stimulus that he gave to the society of Chos?n became a catalyst that brought on the rapid decay of Chos?n. Eventually, the flow of history supplanted the Confucian monarchy with a Democratic Republic. In retrospect of this, HSY can be seen as a forerunning model of 'the modern man', who opened up the door to the modern world.