Matteo Ricci introduced into China the Western theory of soul, a term which he translated as linghun 靈魂. Afterwards, two other Italian Jesuits, Giulio Aleni and Francesco Sambiasi, separately completed two Chinese interpretations of the De Anima (On the Soul), the former privileging the word linghun, and the later, yanima 亞尼瑪, a transliteration for anima. Xia Dachang 夏大常 (Mathias Hsia) is probably the first Chinese person to write specifically on the topic of the soul. However, he used a different term, lingxing 靈性 (human spiritual nature), and also he titled his work “The Theory of Human Nature” (“Xingshuo” 性說). Xia’s work has received little scholarly attention, and this paper aims at investigating how he adopts the Western theory of the soul, why he still uses the concept of lingxing, and which Chinese editions of De Anima or other works written by the Jesuits had influenced him. We shall also see how Xia Dachang uses traditional Chinese sources and Catholic doctrine to support his viewpoint of human nature and how he criticizes theories of human nature within Chinese philosophy. This will enable us to comprehend how Chinese Christians in the Early Qing dynasty understood the theory of the soul and to reflect on the contemporary relevance of this theory in Chinese culture today.