"The movement of heaven is strong and vigorous, and a gentleman strives to constantly strive for self-improvement; the terrain is turbulent, and a gentleman carries things with great virtue." It means: the movement of heaven (i.e., nature) is vigorous and vigorous. Correspondingly, a gentleman should behave like Like the sky, one strives to make progress, is resolute, strives for excellence, and never stops; the momentum of the earth is thick and gentle, and a gentleman should increase his virtues and accommodate all things.

Source

This sentence comes from the "Xiang Zhuan" written by Confucius for the "Book of Changes". Elephants are divided into elephants and baby elephants. The elephant explains the meaning of the hexagrams, and the small elephant explains the six lines. This sentence comes from the "elephant" in the two hexagrams of Qian and Kun.

(Qian Gua) Xiang says: Heaven moves vigorously, and a gentleman strives to constantly strive for self-improvement; (Kun Gua) Xiang says: The terrain is Kun, and a gentleman carries things with great virtue. The previous sentence "Heaven moves vigorously, and a gentleman strives to constantly strive for self-improvement" is more widely circulated. But over the past two thousand years, there have been many people who know it and few people who can understand it. However, there are still different interpretations in the academic community, and there seems to be no generally accepted correct interpretation.

A more popular explanation (reference): The movement of heaven is prosperous and prosperous, and a gentleman should imitate the sky and strive for self-improvement; the situation of the earth is in accordance with the law and Kun, and a gentleman should imitate the earth and be virtuous. Note: The meaning of Kun Xiang is "Shun Cheng".