Kayoiura, located at the most easterly point of Omijima Island, Nagato City, Japan, is a small fishing village where community-based coastal whaling took place from late 1600 to early 1900. Today, more than 100 years since the end of whaling, the community maintains a number of cultural properties, both tangible and intangible, dedicated to the spirits of whales, including prayers for the whales given daily by two elderly Buddhist nuns. This article suggests that these cultural properties convey the former whaling community's ethics and spirituality with a strong sense of reciprocity that acknowledges the undeniable human dependency on other lives. It is argued that such spirituality has an important implication for our understanding of sustainability. Whaling is no doubt one of the most contentious issues in today's environmental debates, where divisive arguments collide over a wide range of issues. Although any study on whaling would play a role in the debate, this article's intention is elsewhere: to acknowledge the importance of ethics and spirituality as intangible cultural heritage and their role in sustainability debate.ACKNOWLEDGEMENTS: I would like to acknowledge the generous support provided by Mr. Fujii, director of the Nagato Whale Museum in organizing the fieldwork in Nagato. His passion, willingness, and commitment to the local community provided immense support for this study. I am grateful for the people at Kayoi who accommodated me and shared their knowledge, experiences, and many stories. I am particularly indebted to obii-sama, the Hosen-an nuns, for allowing me to hear the stories of their lives as well as record the sound around Hosen-an, including their prayers. I wish for the safety and prosperity of the people who live with and care for the natural environment and the spirits of all beings.