In 605 B.C. envoys from the State of Chu presented a giant turtle to the ruler of the State of Zheng. The latter ordered it to be cooked, and was going to share it with his nobles. On his way to the feast, Zi Gong, an official of Zheng, felt his forefinger twitch. He said to his companion Zi Jia: "Whenever this happens it means that I'll surely have the chance to taste something extremely delicious." The ruler of Zheng heard about this, but gave Zi Gong no part of the turtle when it was served. Zi Gong was angry as well as hungry, so he dipped his finger into the tripod that held the cooked turtle, sucked the juice-stained finger, and left. The ruler of Zheng was so angry that he wanted to kill Zi Gong. However, he himself was slain by Zi Gong later.

Later, the expression came to mean taking a share of something one is not entitled to.