The sky goes at four o'clock without saying anything, and the earth goes without saying anything. Interpretation: The sky can't talk, but the seasons alternate, and the earth can't talk, but everything grows.

If you are not indifferent, you can't be clear about your ambitions, and if you are not quiet, you can't achieve your lofty ideals.

Heaven goes at four o'clock without saying a word, and everything comes from the earth without saying a word: Pei Chang's History Book of Shang 'an Prefecture by Tang Li Bai.

Not indifferent, not clear-minded, not quiet, not far-reaching: The Book of Commandments by Zhuge Liang of the Three Kingdoms.

Extended information

Writing background of Pei Chang's History Book of Shang 'an Prefecture:

Li Bai's History Book of Pei Chang of Shang 'an Prefecture was written in 753 A.D., the center of which is to defend Pei Kuan, who defended the history of An 'an Prefecture, that he was slandered and wronged by complaining about his various conduct, such as being generous with money, paying attention to justice, caring for his career and being talented.