A promise worth one thousand in gold
To make good on a promise; to stay true to one's word; to have one's word be honest and reliable
Neutral
如果我们答应别人的事情一定要一诺千金，不能轻易食言 | Rúguǒ wǒmen dāyìng biérén de shìqíng yīdìng yào yīnuòqiānjīn, bùnéng qīngyì shíyán
If we promise to do something for others, we have to be true to our word and cannot lightly renege
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他为人一诺千金，他答应了你，就一定会办好，你尽可放心 | Tā wéirén yīnuòqiānjīn, tā dāyìng le nǐ, jiù yīdìng huì bàn hǎo, nǐ jǐn kě fàngxīn
He's always true to his word. If he promises you something, he'll definitely do it, so you don't have to worry
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True to one's word
Make good on a promise
None
Be careful not to confuse the surname 季 (jì) with the surname 李 (lǐ).
《史记》(Shǐ Jì), or the famous work "Records of the Grand Historian" by 司马迁 (Sī Mǎ Qiān).
At the end of the 秦 (Qín) Dynasty (221 - 207 BC), there lived a noble man named 季布 (Jì Bù). 季布 served under 项羽 (Xiàng Yǔ, or Xiang Yu the Conqueror) and helped him win victories against a warlord named 刘邦 (Liú Bāng). Unfortunately, 刘邦 eventually defeated 项羽 and established the Hàn Dynasty (汉, 206 BC - 220 AD), and he was so enraged at 季布's role under the other warlord that he ordered his arrest. He even threatened to kill the entire families of those who helped 季布 evade capture.
However, this threat was not enough to deter 季布's friends. One family quickly disguised him as a servant and sent him to take shelter at another friend's house. That friend spoke to a local lord on 季布's behalf, and the lord in turn spoke to the emperor. This led to 刘邦 not only clearing 季布's name, but also eventually giving him an official title. Unsurprisingly, 季布's life improved significantly after this.
Now, there was a man from 季布's hometown named 曹邱生 (Cáo Qiū Shēng). 曹邱生 made a hobby of becoming friends with powerful people and leveraging them to make profits. When he heard of 季布's change in status, he immediately decided to visit him. 季布, however, knew of his reputation, was not pleased by 曹邱生's presence. 曹邱生 responded to the poor reception by bowing and lavishing praises on 季布, pointing out that there was a new saying that claimed that "receiving 1,000 pieces of gold paled in comparison to getting a promise from 季布." He informed 季布 that his reputation had spread so far because he had been telling everyone about him.
Hearing this, 季布 had a rapid change of heart, and he invited his guest to stay for several months and gave him many precious gifts. Afterwards, 曹邱生 continued to spread the word about 季布, thus increasing the official's renown even further.