Be alert at night
As a Chinese idiom, the Pinyin is x ī t ì zh ā oqi á n, which means to be diligent and cautious all the time and dare not be lazy. From Yi Qian.
The origin of Idioms
Yi · Qian: "a gentleman works hard all day long. He is vigilant at night. He has no fault."
Idiom usage
Examples
It is the rule that our ancestors have tried, and it is the natural division of ministers. Zhang Juzheng of Ming Dynasty
Be alert at night
serve an emperor and do service for a throne - pān lóng xiù fèng