During the final years of the Western Han Dynasty, Wang Mang seized power and established the Xin Dynasty, but he proved utterly incompetent at governing. Paralyzed by the fear that others might usurp him as he had usurped the Han, Wang Mang trusted no one and insisted on handling every matter personally, no matter how trivial. Worse still, his decrees were issued on a whim, often changing from morning to evening—leaving officials and commoners alike scrambling to keep up with his erratic commands.
In this turmoil, commoners rose in rebellion. The most formidable force was the Green Woods Army, who declared Liu Xuan, a member of the Han imperial clan, as emperor. Meanwhile, another Han descendant, Liu Xiu, seized the opportunity to raise his own troops and pledged allegiance to Liu Xuan.
Later, Liu Xiu led his army to a decisive victory over Wang Mang's Xin forces at Kunyang and was appointed General Who Breaks the Enemy by Liu Xuan. The Lulin army then captured Chang'an and killed Wang Mang. Ordered to attack Handan, Liu Xiu swiftly took the city and executed Wang Lang, who had declared himself emperor. Seeing Liu Xiu's repeated successes, Liu Xuan granted him the title Prince of Xiao.
At that time, the northern regions were not yet fully pacified, so Liu Xiu led his troops northward. In 24 AD, he arrived with a large army at Wu, laying siege to another rebel force, the Tongma Army. After a fierce battle, the Tongma Army was defeated, and hundreds of thousands surrendered to Liu Xiu.
Emperor Guangwu of Han, Liu Xiu, reorganized the surrendered troops, integrating them into his own forces. He appointed the former Bronze Horse Army commanders to official posts, allowing them to lead their original soldiers, demonstrating his trust and strategic magnanimity.
But the generals of the Bronze Horse Army were deeply worried, feeling that since they had once been Liu Xiu's enemies, they would surely face hard times ahead—some even feared Liu Xiu would have them killed.
After learning of their doubts, Liu Xiu took only two attendants and went to inspect the camps of the newly surrendered troops. Seeing Liu Xiu's complete trust and lack of suspicion, these surrendered officers and soldiers happily discussed among themselves:
"Prince Xiao is a man of great sincerity. He treats us with complete openness and trust—how could we not give our lives for him?"
With this, Liu Xiu's strength grew immensely. He later reunified China, established the Eastern Han Dynasty, and became the renowned Emperor Guangwu of Han.
Later, the idiom "Tui Xin Zhi Fu" came to mean treating others with utmost sincerity.
Source: *Book of the Later Han*, Chapter "Annals of Emperor Guangwu"
Meaning of the Idiom: Later, the Chinese idiom "推心置腹" came to describe how treating others with utmost sincerity.