During the Spring and Autumn period, Duke Zhuang of Lu wanted to pass his throne to his favored son Ziban, born of his beloved concubine Meng Ren, but he feared opposition from his other sons and three younger brothers. In 662 BCE, knowing his illness was terminal, the duke cautiously asked his second brother Shuya, "Who should inherit the throne?" Shuya replied, "Qingfu is highly capable and fit to succeed."
Duke Zhuang was dissatisfied and asked his third brother, Jiyou. Jiyou firmly declared, "I am willing to support Ziban as ruler with my life."
Duke Zhuang agreed with Ji You's opinion and expressed disagreement with Shu Ya's view
After Duke Zhuang of Lu died in the eighth month of that year, Ji You installed Ziban as the new ruler. Qingfu, who also coveted the throne, was deeply dissatisfied and conspired with Duke Zhuang's wife, Ai Jiang, to murder Ziban. They then installed Kai, the son of Ai Jiang's sister Shu Jiang and Duke Zhuang, as the ruler, historically known as Duke Min. A little over a year later, Qingfu sent assassins to kill Duke Min as well. The people of Lu, outraged that Qingfu had murdered two rulers in succession, rose up against him. Fearing for his life, Qingfu fled to the state of Qi.
Confucius recorded this history in the *Spring and Autumn Annals*, stating: "Zi Ban died; Prince Qingfu went to Qi."
"Ru Qi" means going to the state of Qi. Qing Fu clearly fled to Qi, so why does the *Spring and Autumn Annals* say he went there? The *Guliang Commentary* remarks, "Nothing is as hidden as what is deeply taboo; what is deeply taboo is concealed." This means that out of avoidance, the truth was deeply buried.
Later, "Hui Mo Ru Shen" evolved into an idiom, used to describe hiding the truth so tightly that no one else knows.
Source: *Guliang Zhuan*, Chapter "Duke Zhuang, Year 32"
Meaning of the Idiom: Later, the Chinese idiom "讳莫如深" came to describe hiding the truth so tightly that no one else knows.