《明史·列传·卷九十一》
皇帝多次生病，郑岳请求皇帝遵循圣祖寡欲勤治的古训，后宫有一定的规制，房事有一定的时间安排，而退朝却去文华殿，裁决章奏，日暮还宫，以养寿命之源。
帝数不豫，岳请遵圣祖寡欲勤治之训，宫寝有制，进御以时，而退朝即御文华，裁决章奏，日暮还宫，以养寿命之源。
The emperor fell ill multiple times, and Zheng Yue requested that the emperor follow the teachings of his ancestors, to decrease his desires and勤治, to impose some kind of order upon the concubines, and to schedule his personal affairs, and not immediately return to the palace after retiring in order to preserve the source of his longevity.