【Source】Sima Qian (Western Han Dynasty), "Records of the Grand Historian: Biographies of Ji Bu and Luan Bu."
【Meaning】"Nuo" means promise. A single promise is worth a thousand pieces of gold. This idiom metaphorically describes someone who keeps their word and is extremely trustworthy.
【Historical Anecdote】
At the end of the Qin Dynasty, in the Chu region, there was a man named Ji Bu. He was upright in character, chivalrous, and always ready to help others. Whatever he promised, no matter how difficult, he would find a way to fulfill it, earning him widespread praise.
During the struggle between Chu and Han, Ji Bu served under Xiang Yu and had devised several strategies that inflicted defeats on Liu Bang's army. After Xiang Yu's defeat, Ji Bu fought his way out of the encirclement alone and began a life on the run. When Liu Bang became emperor, he remembered these events with fury and immediately issued an order to arrest Ji Bu.
However, many people who admired Ji Bu secretly helped him. Soon, Ji Bu disguised himself and became a laborer in the household of a man surnamed Zhu in Shandong. The Zhu family knew he was Ji Bu but still took him in. Later, Zhu went to plead with Xiahou Ying, the Marquis of Runyin. Convinced by Xiahou Ying, Liu Bang not only rescinded the arrest order for Ji Bu but also appointed him as a Langzhong (an imperial attendant). Soon after, Ji Bu was promoted to the position of Grand Administrator of Hedong.
Ji Bu had a fellow townsman named Cao Qiusheng. Upon hearing that Ji Bu had become a high-ranking official, Cao immediately went to visit him. Ji Bu, however, harbored some misunderstanding toward Cao and, knowing he was coming, put on a stern face, preparing to rebuke him and make him lose face. To Ji Bu's surprise, as soon as Cao entered the hall, regardless of Ji Bu's gloomy expression and harsh words, he repeatedly bowed and saluted, eager to chat and reminisce. Cao said, "We are both from the Chu region; as fellow townspeople, we should cherish our local bond. I've heard a saying circulating in Chu: 'To gain a thousand taels of gold is not as good as gaining a single promise from Ji Bu.' How have you earned such an excellent reputation throughout the Liang and Chu regions? Precisely because you are my fellow townsman, I have been proclaiming your virtues everywhere! Why are you unwilling to see me and become friends?" After hearing Cao Qiusheng's words, Ji Bu's misunderstanding vanished instantly, and the two became close friends from that point on.