This sentence comes from Chapter 76 of Romance of the Three Kingdoms, which happened when Guan Yu was trapped in Maicheng. It means that jade can be broken, but it cannot change its white nature; Bamboo can be burned, but it can't destroy its joints.
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Guan Yu said seriously, "I am a soldier in Xie Liang, and my master treats me like a brother. Are you willing to betray your loyalty to the enemy? " If the city is broken, it will die. Jade can be broken without changing its whiteness, bamboo can be burned without destroying its knots, and although it is dead, its name can be hung on bamboo and silk. Don't say anything, please leave the city as soon as possible, I want to fight with Sun Quan to the death! "Jin said," The marquis of Wu wants to make friends with the princes of Qin Jin and help Cao and Han, but he has no other intention. What is your obsession? Before he finished speaking, Guan Ping drew his sword and wanted to cut it.
Gong said, "My brother Kong Ming is in Shu, helping your uncle. If you kill him now, it will hurt his brother's feelings. " So he ordered the left and right to be expelled from Zhu Gejin. Jin was ashamed and got on the horse and went out of town. When he met the marquis of Wu, he said, "My heart is as hard as stone. Don't say anything." Sun Quan said, "What a loyal minister! What is it like? " Lv Fan said, "Please forgive me." Power is to command it. Fan Yi's image is a "divining master of the earth and water", which is more obvious that the main enemy is far away.
Quan asked, "The divination is the main enemy running away. What's your strategy for catching them? " Meng Meng smiled and said, "This divination is the right opportunity. Although Guan Gong has wings to fly to the sky, he can't fly out of my net! "