During the Eastern Han Dynasty, a talented scholar named Zhang Jian from Gaoping County in Shanyang Commandery (present-day southwest of Zou County, Shandong) was recommended for an official post, but he feigned illness to avoid serving because he disapproved of the local inspector.
At that time, Zhai Chao, the governor of Shanyang Commandery, admired Zhang Jian's reputation for talent and invited him to serve as the Eastern Inspector, responsible for overseeing the counties within the commandery. Knowing that Zhai Chao was an incorruptible official, Zhang Jian accepted the position.
In Shanyang Commandery, the eunuch Hou Lan used his imperial favor to bully locals, seizing homes and stirring outrage.
Outraged by the eunuch Hou Lan's corruption, Zhang Jian submitted a memorial to Emperor Huan of Han demanding severe punishment. But the memorial fell into Hou Lan's hands. After waiting in vain for a reply, Zhang Jian took action himself. With Zhai Chao's backing, he personally led a raid to destroy Hou Lan's "longevity tomb"—a lavish mausoleum built while Hou Lan was still alive—and confiscated all his ill-gotten wealth.
Hou Lan, grinding his teeth with rage, bided his time for revenge. He colluded with Zhang Jian's fellow villager Zhu Bing to falsely accuse Zhang Jian of conspiring with 24 men from the same commandery to rebel. The imperial court then issued a warrant for Zhang Jian and the others, forcing Zhang Jian to flee that very night.
During that time, the people harbored deep hatred for the eunuchs, and Zhang Jian had punished Hou Lan, earning himself a stellar reputation. Wherever he went, people would risk their lives to protect him.
One day, the desperate fugitive Zhang Jian sought refuge at the home of his close friend Kong Bao in Lu Commandery. Finding Kong Bao away, Zhang was instead received by Kong Bao's younger brother, the sixteen-year-old Kong Rong. After Zhang Jian departed, soldiers arrived on his trail and arrested Kong Bao, Kong Rong, and their elderly mother.
During the interrogation, the mother and her two sons each insisted on taking full responsibility, leaving the officials utterly baffled. In the end, the authorities had no choice but to convict Kong Bao, while Zhang Jian remained at large.
Later, people used the idiom "Seeking Shelter at Any Door" to describe the urgent need for temporary refuge during flight or hardship.
Source: *Book of the Later Han*, "Biography of Zhang Jian"
Meaning of the Idiom: Later, the Chinese idiom "望门投止" came to describe the urgent need for temporary refuge during flight or hardship.