“比干是暴君紂王的叔父，也是商朝的丞相，為人忠耿正直，經常勸諫被妲己迷惑的紂王。因此令妲己懷恨在心。妲己對紂王假說自己心絞痛復發，需以七竅玲瓏的心作藥引才能治愈，而忠臣的心必定是七竅 玲瓏，於是紂王便命人向比干剖腔取心。姜子牙得知此計，遂以法術護住比干，讓比干無心卻仍能生存，並囑比干被取心後要盡快離開殷商。比干把心挖出，逃開時遇到一 個賣空心菜的老嫗，在市集叫賣空心菜。比干路過時聽見，趨前一問何為空心菜，老嫗曰：「民婦賣的是無心菜。」比干曰：「人若無心如何？」老嫗答：「菜無心可吃，人無心當死。」比干驚覺自己無心，遂倒地死去。”
"Bigan (比干) was the uncle of tyrant Zhou (紂王) and the prime minister of the Shang Dynasty (商朝) as well. He was a man widely renowned for his uprightness and loyalty. Since he been pressurizing tyrant Zhou to stay away from his concubine Daji (妲己) (a fox spirit in disguise) all along, tyrant Zhou and Daji had a deep grievance against Bigan and was trying to get rid of him every now and then. One day, Daji faked a heart attack in front of Emperor Zhou. When asked if there any way to cure heart disease, Daji said to the Emperor there's only one cure in this world and that is the heart of a righteous and loyal minister (implying Bigan's). Hearing this, the tyrant sent his servants right down to Bigan's residence and demand his heart.
Jiang Ziya (姜子牙), a demigod as well as a friend of Bigan, foresaw all this coming. He told Bigan not to worry and surrender his heart to the tyrant, given that he would put a spell on Bigan to protect him. Jiang further instructed Bigan to run away as soon as possible and talk to no one on his way. However, on his leaving way, Bigan came across a old woman touting water spinach, not knowing what that vegetable she was selling, Bigan curiously asked the woman what it was and she said to him it was hallow vegetable 空心菜 (lit. vegetable without heart). "What if a man without heart?" Bigan asked without realizing the danger still. The old woman murmured, "vegetable without heart is edible, but man without heart is lethal." Wtih this, the spell lost its magic and failed, Bigan suddenly came to realize that he is now a man without heart. Thereupon, he fell to his death right on the spot."
Fengshen Bang, The Investiture of God (trans. by CXB)