A letter of confidence
Baozhu Zhixin, a Chinese idiom, Pinyin is B à ozh à x à n, which means to stick to the letter. It's from Zhuangzi's stealing Zhi.
The origin of Idioms
Chuang Tzu's stealing feet: "Wei Sheng and the woman expect to live under the beam. If the woman doesn't come, the water will not go, and she will die holding the beam."
Idiom usage
Keep one's word. Examples Yu Biyun's selected interpretation of Ci Poetry in Tang, Five Dynasties and two Song Dynasties: long guarding Wei Sheng's letter of holding a pillar, reducing Shen Lang's girdle and expressing his true feelings. The sixth chapter of Hui Qiyuan's "graceful Ci" and "historical records - biographies of Su Qin": "the letter is like the end of life, and the woman is under the beam. If the woman does not come, the water will not go, and she will die holding the pillar." Tang Libai's poem "a long journey of cadres" says: "if you always hold a pillar, you can't go to the watchtower."
A letter of confidence
having maps on the left and history books on the right -- a home library - zuǒ tú yòu shū
resign from office and return to one 's native town - gào lǎo huán jiā
eulogize the past at the expense of the present - sòng gǔ fēi jīn