Cui Zhu and Qing Feng Install Duke Jing and Force the Covenant on the People, with Yan Ying Refusing to Swear

In 548 BC, Cui Zhu, a powerful minister of the state of Qi, murdered Duke Zhuang after discovering the duke's adulterous affair with his wife. Cui Zhu and his ally Qing Feng then installed Duke Zhuang's half-brother, Chujiu, as Duke Jing, and made themselves chief ministers. To consolidate power, they forced the officials and people of Qi to participate in a blood covenant at the Grand Temple, swearing allegiance to the Cui and Qing families and vowing death to any who opposed them. Yan Ying, a senior official renowned for his righteousness, attended but refused to repeat the oath. He declared to heaven that he would only align with those loyal to the ruler and beneficial to the state, thereby refusing to endorse the usurpers. His act of quiet defiance was a moral protest against tyranny, demonstrating that legitimacy cannot be coerced. This incident was recorded in the Zuo Tradition and became a classic example of an upright minister resisting illegitimate authority.

No formal judicial trial was conducted. In practice, Yan Ying altered the covenant oath to pledge loyalty to the ruler and the state rather than to the Cui and Qing factions. He was not executed or imprisoned, a tacit acknowledgment of the limits of the usurpers' power and of Yan Ying's moral authority. Subsequently, Cui Zhu's family perished in internal strife and Qing Feng was driven into exile, a turn of events that historically vindicated Yan Ying's position.

The central dispute was whether an oath extracted under coercion by usurpers could be considered legally and morally binding, and whether Yan Ying's refusal to swear the imposed covenant constituted an act of treason or justifiable civil disobedience. It raised fundamental questions about the validity of forced allegiances and the conflict between personal conscience and the demands of de facto rulers.

Yan Ying's stance became an enduring symbol of loyalty to the state over allegiance to factional power, embodying Confucian ideals of remonstrance and righteousness. His declaration that he would only support what was loyal to the ruler and beneficial to the state entered Chinese political and ethical discourse. The case has been celebrated in literature and historiography as a model of moral courage, influencing later concepts of legitimate resistance to tyranny and shaping the archetype of the upright minister.