  Imperial patronage enhanced the prestige of the Laozi and enlarged its scope of influence. In 733 C.E., the emperor Xuanzong decreed that all officials should keep a copy of the Daodejing at home and placed the classic on the list of texts to be examined for the civil service examinations (see, e.g., the report in the official Tang history, Jiu Tang shu 8). In religious Daoism, recitation of the Daodejing is a prescribed devotional practice and features centrally in ritual performance. The Daodejing has been set to music from an early time. The term “Laozi learning” (Laoxue) has come to designate an important field of study. A useful work in Chinese that sketches the major landmarks in this development is Zhongguo Laoxue shi (A History of Laozi Learning in China) (Xiong Tieji, et al. 1995); a follow-up effort focusing on Laozi scholarship in the twentieth century by the same lead author was published in 2002.