對於臺灣島上土著民俗的文化現象，在清代官宦文人的眼裡，頗具多元族群的特色和異鄉情調，是官私修志書與私人詩文集、筆記裡，必要的采風記錄。尤其是，與漢移民生活區域交疊的平埔熟番，其奇風異俗，常見清代文獻裡互相援引。早在明萬曆年間，就記載臺灣土著產子浴水的現象。清代領臺後，歷來文獻更清楚顯示，從北部到中、南部，都曾記錄着這種異於漢俗的平埔族習慣。這些文獻特別強調，平埔族相信溪水淋浴，具有去病避災的功能和作用，這已成為他們日常生活文化的一部分。 平埔族原本有傳統信仰與文化，但是因應生存環境的實際變化，由此風俗習慣也跟着發生一些轉變。然而，清代少數私人筆記與信函，卻指出這種平埔族習俗，可能受到荷據時期基督宗教的影響。因此，筆者回溯西元1624 至1662 年間西班牙人與荷蘭人相關檔案報告，發現這項習俗的形成背景，與當時天花傳染病的疫情有關。進而，察覺平埔族對疾病的傳統認知，可能吸納了當時基督宗教的傳統疾病觀。最後，眾多因素使得基督宗教未能正確地深入平埔族的理解思維內，以致於西班牙人與荷蘭人相繼離臺後，平埔族繼續以這種更動過的疾病文化觀，在歷史長河中，轉化為集體記憶與日常的生活習慣。筆者認為這項平埔族習俗，可能將基督宗教的洗禮聖事，混淆了身體療病去災的俗世概念，形成了一種生活慣性的模仿動作和行為，卻成為清代歷來文獻裡番俗書寫的特色之一。

When the Qing dynasty officials traveled to Taiwan, the exotic cultural phenomena of the aboriginal people became a favorite theme in their writings. Customs of the Pingpu “tamed aboriginals,” in particular, were cited repeatedly in essays or anecdotal anthologies. Remarks of natives in Taiwan bathing after childbirth were offered in the Ming Wanli era. This Pingpu custom that goes against the Han practice had been documented throughout the Qing dynasty. Many of the writers emphasized that the Pingpu people believed that bathing in streams drove away evil spirits and diseases, and that it had become part of their culture. Though the Pingpu traditional culture and belief could have adapted to the actual changes of living environments, private anecdotes and correspondences indicate that belief in the efficacy of bathing might have been influenced by Christianity introduced during the Dutch era. I have since combed through the Spanish and Dutch archives between 1624 and 1662, and learned that the background of this custom appears to be related to the epidemic of smallpox, and that the traditional Pingpu cognition of diseases have integrated the Christianity concepts of disease. Due to various reasons, the correct Christianity notion (of baptism) failed to instill into the Pingpu cognitive thinking. After the Spanish and Dutch left Taiwan, the Pingpu people turned this altered cognition of diseases into their collective memory and daily custom. I argue that the Pingpu people confuse Christian ritual of baptism with the folklore of water’s purifying power. They developed an imitative practice accordingly. It has become one distinguishing feature of writings about aboriginal customs since the Qing dynasty.