During the Spring and Autumn Period, Jin Xiangong's son Zhong Er fled to Chu. King Chu Cheng took him in and entertained him. He promised that if there was a war in Chu Jin, the Jin army would stay away. Later, Zhong Er returned to the State of Jin with the help of Qin Mugong. The State of Jin supported the contradiction between Song and Chu, and Zhong Er stayed out of the house, luring the enemy deeper and winning.