In the Spring and Autumn Period (770-476BC) of China's history, Duke Xiao was the monarch of the State of Jin . His eldest son, Shen Sheng should have inherited the throne on the death of his father. The King very much doted on his concubine Li who wanted to make her own son the crown prince. So she killed the crown prince Shen Sheng by scheme. Soon afterwards she began to persecute Chong'er, the son of the crown prince. As soon as Chong'er got wind of this, he fled abroad together with his henchmen.

On the way of exile Chong'er and his henchmen went through all kinds of hardships and difficulties. One day they came to a remote and uninhabited place where Chong'er, worn out and hungry, suddenly, collapsed down the ground and was not able to go a step further. Actually, he was starving and dying.

His henchmen searched for a long time but could find nothing to eat. So everyone was deeply worried. Seeing this, Jie Zitui, an official following him, retreated to a secluded place and cut a piece of flesh off his thigh. He cooked a bowl of soup with his flesh and held it to Chong'er in his hands.

Chong'er devoured the soup ravenously and then recovered his vitality gradually. When he asked where they got the flesh, the officials looked at Jie Zitui whose gown was stained with blood and told Chong'er everything with tears in their eyes.　

Chong'er was so moved that, with all sorts of feelings welling up in his heart, he embraced Jie Zitui and said, shedding tears, "What shall I do to repay you?" "You have tasted to the full the bitterness of the people through your exile. I hope you will be a king clear and bright in the future." replied Jie.　

Nineteen years later Chong'er finally became the King of Jin State who was named Jin Wengong in China's history. After his ascending the throne, Jin Wengong conferred titles and awards to the meritorious officials who had followed him in exile, but only to forget Jie Zitui who had sacrificed the flesh of his leg.

Quite a few people felt indignant at the injustice done to Jie Zitui. They advised him to see the king and ask for awards. Jie Zitui, however, disdained very much those who contended for merits and asked for rewards. He tidied up his things and went quietly with his mother to the Mianshan Mountain to live in seclusion.　

When Jin Wengong heard of that, he was only too ashamed and regretful. Bringing his men, he made a personal call to Jie's house to invite him, but only to find the door was locked. Some neighbors said that Jie was not willing to be an official and had gone to the Mianshan Mountain, carrying his mother on his back.　

The Mianshan Mountain was very high with a dangerous and difficult mountain pass and a dense forest. And it was by no means easy to look for Jie and his mother. Someone offered an advice of setting a fire to force Jie out. Jin Wengong readily agreed. So a soaring fire immediately spread from the three sides of the mountain.　

The fire burned all over the Mianshan Mountain, yet not a shadow of Jie was found. When the fire went out, however, people found Jie dead sitting under an old willow tree with his mother on the back. Seeing this Jin Wengong felt unbearably painful and nearly cried his heart out!　

When putting Jie's dead body into the coffin, people found in a hole of the tree trunk a letter written by Jie in his own blood which read, I cut off my own flesh to dedicate to you only to express my devotion. And I only wish my king will always be clear and bright. If you will bear me in mind, make self-examination whenever you recollect me."

The letter written in blood accompanied Jin Wengong to spend the rest of his life. In order to keep in memory of Jie Zitui, he issued an order to turn the name of Mianshan Mountain into Jieshan and make the day Haishi Day (or Cold Food Day). And on the Cold Food Day every year, no fire or smoke was allowed and people should eat cold food for the whole day.

On the Cold Food Day the next year when Jin Wengong led his officials to hold a memorial ceremony for Jie up the mountain, to his surprise, he found the dead old willow tree had revived with luxuriant foliage. He braided a wicker ring and put it on his head to express his sincerity. And the officials followed his example one after another.

There and then Jin Wengong bestowed the old willow tree the name of Willow Clear and Bright. As soon as he returned to the court he made known all over the country that the day after Cold Food Day was fixed as the Clear and Bright Festival, or Qingming Festival in Chinese. The festival and customs were thus handed down from generation to generation. In addition, people began to visit Jie Zitui's tomb and pay their respects to him.

It was not until the Qing Dynasty (1644-1911) about 300 years ago that the practice of Hanshi (or eating cold food) was replaced by that of Qingming, which had now become an important occasion for people to offer sacrifices to their ancestors.