During the Warring States period, when conflicts raged between states large and small, the state of Zou clashed with Lu in a fierce battle. The result was a devastating defeat for Zou, with many of its generals killed on the field.
When the war ended, Mencius happened to arrive in Zou. Duke Mu of Zou met Mencius, told him about the defeat, and said:
"In this battle, dozens of my generals were killed, yet the common soldiers who witnessed it showed no concern—not a single one fought to save them. They watched their commanders die on the battlefield with such indifference that it fills me with rage. I wish I could execute them all, but there are too many to kill; yet if I spare them, I cannot quell my fury. What do you advise I should do?"
Mencius thought for a moment and replied, "Your Majesty, have you ever considered why this happens? As I understand it, your kingdom suffered a severe famine two years ago. The scorching sun withered every crop. Countless elderly and frail people starved to death in the wilderness, while the strong and able-bodied fled their homes to seek refuge elsewhere. Yet your granaries were overflowing with grain, and the state treasury was abundantly stocked. The local officials never reported the people's suffering to you. They sat high above the commoners, indulging in lavish feasts and endless pleasures."
Mencius then shifted his tone and pressed, "Your Majesty, do you recall what Confucius' disciple Zengzi once said? He warned, 'Be cautious! How you treat others is how they will treat you!' If your officials treat the people this harshly, it stands to reason that when the commoners get their chance for revenge, they will treat those officials the same way."
Mencius, noticing the Duke of Zou nodding slightly, concluded, "So, I believe Your Majesty has no need to blame the common people, much less punish them. Only by practicing benevolent governance within the state and teaching the people with righteousness and humanity will your subjects share your heart and mind, willing to dedicate their very lives to defend the nation."
Duke Mu of Zou, deeply impressed by Mencius's reasoning, began implementing benevolent governance in his state, and Zou gradually grew prosperous and strong.
The idiom "out of the pan, into the fire" originally meant how you treat others is how they will treat you. Later, it came to describe someone whose words and actions are inconsistent.
Source: *Mencius*, Chapter "King Hui of Liang"
Meaning of the Idiom: Later, the Chinese idiom "出尔反尔" came to describe how you treat others is how they will treat you.