What elements make Korean religions distinctive? This is an issue that has attracted a lot of attention from many scholars in the field. What would be an effective avenue to approach the ways in which external religions are adapted or transformed to Korean society and culture? In this article, Hur suggests that the task of tackling this question can benefit from a border-crossing approach, particularly through comparison with Japanese religions that offer a range of contrasting features. In order to illustrate this, Hur offers two examples that sharply distinguished Korean religions from Japanese religions in early modern times. One is the value of filial piety which dominated Korean Confucianism but was almost invisible in Japanese Confucianism. The other is Buddhism's role in funerary rituals and ancestor worship: Buddhism in Chosŏn Korea was kept at bay from the dominant ritual arena of ancestor-related rituals; in contrast, Buddhism in Tokugawa Japan was the central agent of funerary rites and ancestor worship rituals. Hur suggests that border-crossing, comparative approaches that involve Japanese cases can contribute to de-localizing Korean religions and, at the same time, to localizing Korean-ness found in Korean religions in the context of society and culture.