This paper examines the relationship between the tendency of the unity of the meditative and doctrinal approaches 教禅融合 in Chinese Buddhism from the Tang to Song dynasties and the establishment of the Zongjing lu 宗鏡録, and then analyzes the theoretical background of the reason why the Zongjing lu focuses on Huayan’s dharmadhātu theory and the meaning of the concept of dharmadhātu in the Zongjing lu and its relationship with the one mind 一心. The following three conclusions were reached.
First, the trend towards the Chan-ization of Chinese Buddhism became more pronounced. There is a Chan tradition that emphasizes the one mind. Based on this, Yanshou 延寿 accepted Zongmi’s 宗密 idea of the harmony of the meditative and doctrinal approaches 教禅合致, worked to unify the doctrines of the various sects through ‘the one mind sect’ 一心宗, and compiled the Zongjing lu.
Second, the interpretation of dharmadhātu in the Zongjing lu is a synthesis of the discussions of various schools of thought, centering on the teachings of Zongmi.
Third, it maximizes the Chan tradition of ‘以心為宗’ （to consider mind as the implicit truth） and includes the dharmadhātu doctrine of the Huayan school in ‘能詮’ （to express in words, the efficacy of an explanation or a commentary） that is used to articulate the one mind. This is arguably the greatest theoretical contribution that the Zongjinglu gives to the view of dharmadhātu.
