Source: Thirty-three Years of Zuo Zhuan by Zuo Qiuming in the Spring and Autumn Period.
Excerpt from the original text: Merchants from Slippery and Zheng will meet in Zhoushi. Taking Wei Xian and Niu Shi as teachers, he said, "I have heard that my son will step out of our city, and those who dare to follow will not avoid our city. If you are overwhelmed by followers, you will have a day of accumulation when you are alive, and you will have a night of defense preparation when you walk. "
Translation:
When Qin Jun arrived in Sliding State, Gao Xian, a businessman from Zheng State, was going to Zhou Zhou to do business. When he met Qin Jun, he first gave Qin Jun four cooked cowhide as a gift, and then sent twelve cows to reward the army. He said, "I heard that you are going to March through our city, and I will reward your followers." Our city is poor, so for your entourage to stay here, prepare a day's supply when you stay, and prepare a night's defense when you leave. "
Extended data
The story happened in the Spring and Autumn Period. In 628 BC, he died and the son Lan succeeded to the throne. The decision to expand eastward took advantage of the opportunity of Jin State to destroy Zheng.
So he ordered the generals Meng, Bai and Bai to lead 400 chariots to attack Zheng. In the second year (627 BC) in February, Qin Jun led the main force to the territory of Slip State (now Yanshi and Gongxian in Henan Province) under the State of Jin.
When I arrived in Sliding State, I met a businessman from Zheng State, who was also very famous. His name was Gao Xian. So he pretended to be Zheng's envoy and gave four cowskins and twelve cows, suggesting that Zheng had already predicted the attack.
At the same time, he quickly sent someone back to Zheng to tell him. Meng, the king of Qin, thought that Zheng was ready, so he led his troops to wipe out the slippery country and returned, thus avoiding Zheng's national subjugation. Zheng Mugong wanted to reward Xian Gao for saving the country, but he refused.
References:
Baidu Encyclopedia-Gao Xian Shen Shi