During the Spring and Autumn Period, Jin, Song and other countries 12 jointly attacked Zheng, and Zheng had to make peace with Jin. Zheng gave money, jewels and beautiful women to Kim. Jin Wengong gave tributes to ministers for pleasure. Jiang Wei advised Duke Mourn of Jin not to just enjoy himself, but to be prepared for danger in times of peace. Jin Wengong thought what he said was reasonable and adopted his suggestion.
Source "Zuo Zhuan Xiang Gong Eleven Years": Be prepared for danger in times of peace.
Shiduju: in; Thinking: thinking. Although I am in a safe environment, I also think about the possibility of danger. It means to be prepared for emergencies at any time.