During the Warring States period, King Min of Qi had a young attendant named Wangsun Jia, a member of the royal clan who entered palace service at fifteen. His doting mother would always urge him to return early, and if he was late, she would anxiously lean against the gate, sometimes even waiting at the alley entrance.
In 284 BC, King Zhao of Yan sent General Le Yi to attack Qi, swiftly capturing its capital Linzi. King Min of Qi fled in panic to Ju City. Wang Sunjia, who had been serving as the king's attendant, was not by his side when the invasion struck. Upon hearing the news, he rushed to find his sovereign but searched everywhere in vain. Dejected and helpless, he returned home.
His mother saw him and asked, "The Yan army has breached the city. Why didn't you stay by the king's side to protect him? What are you doing back here?" Wang Sunjia replied, "I was not with the king, and now I have no idea where he has fled!"
His mother was furious and scolded him, "Son, you leave early and return late every day, and I stand by the door watching for you. When you come home late, I wait for you at the alley entrance. Now you are the king's attendant, yet when he left, you had no idea where he went. What are you even coming back for?"
Wang Sunjia felt deeply ashamed after hearing his mother's words and immediately left home to search for King Min of Qi. Learning that the king had fled to Jucheng, he rushed there. Just as he arrived, a Chu army led by General Nao Chi—summoned by King Min to aid Qi—also reached Jucheng. But instead of helping, Nao Chi seized the opportunity to kill the king. Filled with fury, Wang Sunjia climbed to a high point in the city center, raised his arm, and shouted to the crowd.
“Nao Chi threw our Qi state into chaos and murdered our king—this is an irreconcilable enmity! Anyone willing to join me in killing Nao Chi, bare your right arm and follow me!”
Hearing this, the people of Ju City bared their right arms, seized weapons, and under Wang Sunjia's command, stormed the Chu camp, killing Nao Chi. Soon, they found King Min's crown prince, Fazhang, in the city and hailed him as their new ruler. For his valor, Wang Sunjia was appointed a high minister by the new King Xiang of Qi.
Later, the idiom "Leaning by the Door and Gate" came to symbolize a loving mother or elder's longing and yearning for their child.
Source: *Strategies of the Warring States*, Chapter "Qi Strategy VI"
Meaning of the Idiom: Later, the Chinese idiom "倚门倚闾" came to describe a loving mother or elder's longing and yearning for their child.