Since their very first entry into the Ming empire (Jesuits 1580s, Franciscans 1630s), Christian missionaries produced an extensive body of testimonies on this exotic and unknown territory, in which they described Chinese history, philosophy, nature, culture, religions, society, and people, including Chinese food, culinary practices, and habits. This extensive corpus of missionary documents not only discussed "things Chinese" but also interpreted this unknown country for their European readers in a process our current scholarship has deemed as "transcultural translation", during which the foreign culture is explained using familiar European terms. In my article, I focus on one particular aspect of food intake, or rather its voluntary absence: the practices of ecclesiastical fasting. I analyse how the first Jesuit and Franciscan missionaries understood fasting in the particular context of Chinese and Japanese culture and, more importantly, what obstacles and dilemmas they had to face in establishing it in their missionary work. I then relate these doubts and questions to contemporary missionary casuistry and moral theology. Finally, I explore ecclesiastical fasting as a compelling symbol of Christianity's encounter with the alien spiritual and cultural idioms of China (and Japan). I argue that it exemplifies the nature of the inter-cultural and inter-religious confrontation, displaying the inevitable difficulties inherent in rendering the Christian message. As far as the methodology is concerned, I explore some central assumptions of transculturality, transcultural translation, and Otherness, though I also point out the potential flaws and deficiencies of these perspectives when applied to this textual material. However, I do not aim at establishing an unambiguous methodology for dealing with these sources; my intention is rather to emphasize the absence of a reliable methodological approach for Early Modern missionary documents. [ABSTRACT FROM AUTHOR]