During the Spring and Autumn period, Wu Can of Chu and Zi Chao of Cai were close friends. Their sons, Wu Ju and Shengzi, grew up together, forging a deep friendship that spanned two generations.
When Wu Ju grew up, he married the daughter of Prince Mou. In the thirteenth year of King Kang of Chu's reign (547 BCE), Prince Mou committed a crime and fled the country. Though Wu Ju had nothing to do with the prince's escape, rumors began to swirl, and fearing he might be implicated, he hastily fled to the state of Zheng.
At dawn, Wu Ju rose early, shouldered his simple luggage, and prepared to continue his escape to the state of Jin. As he reached the outskirts of Xincheng, the capital of Zheng, he suddenly heard someone calling:
"Wu Ju! Wu Ju!"
He turned around and was both surprised and delighted to see that the person calling him was Shengzi, an old friend he hadn't seen in years. He happily ran over and said,
"Master Sheng, how did you end up here?"
Two close friends suddenly met on foreign soil, overcome with emotion. They plucked roadside thorns to spread on the ground, sat facing each other, and took out dried provisions to eat and talk. Wu Ju recounted his misfortunes, tears streaming, and said:
"I know nothing of my father-in-law's affairs. I am completely innocent. Forced to leave Chu today, I have no idea when I might return home!"
Shengzi heard this and comforted him, saying:
"Don't worry! I'm going to the State of Jin this time too, so we can travel together. Stay in Jin for now, and I'll do my utmost to help you return to the State of Chu!"
Wu Ju was deeply moved by his old friend's profound loyalty. Thanks to Shengzi's efforts, Wu Ju finally returned to the state of Chu.
Later, the idiom "Ban Jing Dao Gu" came to describe deep nostalgia for one's homeland and profound friendship between companions.
Source: *Zuo Zhuan*, "Duke Xiang's 26th Year"
Meaning of the Idiom: Later, the Chinese idiom "班荆道故" came to describe deep nostalgia for one's homeland and profound friendship between companions.