After Lü Dongbin became an immortal, he once passed by a river and saw a man drowning. He pulled the dead body out of the river, killed a dog nearby, and used its heart to revive the man. Unexpectedly, when the man woke up, he cursed angrily: “I wanted to die, why save me?” The dog saw Lü Dongbin doing such a kind deed and still bit him, which is used to criticize people who don’t recognize kindness.
Not really, it’s just a dog
Lü Dongbin among the Eight Immortals
No, it just refers to the animal dog
Yes, biting Lü Dongbin is actually an allusion. Before Lü Dongbin became an immortal, he was a scholar. He had a fellow townsman friend named Gou Yao. Gou Yao’s parents had both died, and his family was poor, but he was honest and a sincere gentleman, diligent in his studies. Lü Dongbin admired him greatly, swore brotherhood with him, and invited him to live in his house, hoping he would study hard and have a bright future. One day a guest came to Lü Dongbin’s home and saw Gou Yao’s talent and diligence in studying, so he wished to marry his sister to him. Lü Dongbin worried that Gou Yao might be distracted by women and lose focus on his studies, so he devised a plan — for the first three days of their marriage, Lü Dongbin demanded to sleep with the bride first; Gou Yao, being dependent on Lü Dongbin, had no choice but to agree. After three days, Gou Yao discovered Lü Dongbin only read at night and left at dawn. Only then did he understand Lü Dongbin’s intention! Later, Gou Yao passed the imperial exams and became a high official. One year, Lü Dongbin’s house caught fire, and all his property was burned down. Lü Dongbin and his wife went to live with Gou Yao for a few months, but Gou Yao would not give him a single coin. Lü Dongbin sighed deeply.
Biting Lü Dongbin is actually a well-known story. Before Lü Dongbin became an immortal, he was a scholar. Among his friends was a fellow townsman named Gou Yao. Gou Yao lost both parents and had a poor family background but was honest and diligent. Lü Dongbin admired him, swore brotherhood with him, and invited him to live at his home, hoping he would study hard and succeed in the future.
One day, a guest surnamed Lin came to Lü Dongbin’s family. Seeing Gou Yao’s talent and diligence, he told Lü Dongbin he wanted to marry his sister to Gou Yao. Lü Dongbin feared Gou Yao might be distracted by marital pleasures and refused. Unexpectedly, Gou Yao himself eagerly accepted the match upon hearing Miss Lin was beautiful. After much thought, Lü Dongbin agreed and told Gou Yao: “Since you have made up your mind, I won’t stop you, but after marriage, I want to sleep with the bride for the first three nights.”
Gou Yao was shocked. Being dependent on someone, how could he refuse? Moreover, the wedding expenses depended on Lü Dongbin’s family since Gou Yao was poor. After thinking it over, he gritted his teeth and agreed. On the wedding day, Lü Dongbin was busy preparing everything happily, but Gou Yao hid away for shame. At night, after the guests left, Lü Dongbin entered the bridal chamber.
The bride wore a red veil and sat by the bed. Lü Dongbin didn’t lift the veil or speak, just sat under the lamp reading. Miss Lin waited until midnight, but her husband did not come to bed, so she went to sleep wearing clothes. At dawn, the husband was already gone. This happened for three nights, which greatly pained Miss Lin. As for Gou Yao, after enduring the three days, he just entered the bridal chamber and saw his wife sadly crying and asking, “Why have you not come to bed for three nights, only reading by the lamp, coming at night and leaving at dawn?” This question stunned Gou Yao.
The bride lifted her head, even more amazed: why was her husband suddenly a different person? After a long moment, the couple realized the truth. Gou Yao stomped his feet and laughed loudly, “So brother fears I would be distracted by pleasure and forget my studies, and used this method to encourage me!” Miss Lin was also pleased and full of respect for Lü Dongbin. The couple said: “Brother Lü, we will definitely repay your kindness.” Years later, Gou Yao passed the imperial examination and became an official.
The couple tearfully said goodbye to Lü Dongbin’s family and went to take their posts.
No, it’s because dog bites Lü Dongbin means not recognizing a kind heart, used to scold ungrateful people. The Erlang God’s Howling Celestial Dog descended without permission to harm people. Lü Dongbin, just beginning his cultivation, was ordered to subdue the dog with the magical treasure “Cloth Painting.” After the Howling Celestial Dog was trapped inside the treasure, Lü Dongbin worried it might be turned to ashes trapped within, so he released it out of compassion, but the ungrateful dog bit him.
Lü Dongbin: One of the legendary Eight Immortals
It’s not a person; it’s a saying, followed by the rest: not recognizing a kind person’s heart. It means if you help someone out of difficulty, they don’t appreciate it and instead turn against you.
I think so, because it means not recognizing kindness
Lü Dongbin is an immortal, one of the Eight Immortals
Yes, Lü Dongbin is a person
Legend has it that Lü Dongbin was a wealthy merchant, kind and charitable, who pitied the poor and old. One winter, he met a wandering youth named Gou Yao and took pity on him, adopting him to study diligently and aim for success in exams. Gou Yao was truly hardworking, making progress daily. A year later, before exam day, a friend surnamed Lin came.
This friend saw Gou Yao’s talent and proposed marrying his daughter to him. Afraid it might distract Gou Yao, Lü Dongbin hesitated and let Gou Yao decide. Surprisingly, Gou Yao agreed eagerly. The Lin guest was pleased and wanted them to marry immediately. Lü Dongbin told Gou Yao that after marriage, for the first three nights, they were forbidden to enter the bridal chamber and must study all night, while he himself supervised.
Lü Dongbin arranged a grand wedding. After the guests left, Lü Dongbin sent Gou Yao to study while he entered the bridal chamber to read. The bride waited under the veil until late but her husband never came to bed, so she dressed and went to sleep. This continued three days. On the fourth day, Gou Yao finally entered the bridal chamber. After explaining their respective three-night experiences, they both realized Lü Dongbin’s good intentions: he truly wanted Gou Yao to succeed in the exams.
Exam day arrived, and Gou Yao passed as the third top scorer and went to serve as an official elsewhere. More than a year later, Lü Dongbin’s house caught fire and all wealth was lost. He and his family had to live in a shabby hut. He went to find Gou Yao for help. After much hardship, he found Gou Yao’s mansion. Gou Yao sympathized and welcomed him warmly but never brought up lending money for business. After months, Lü Dongbin received no money.
Lü Dongbin sighed, “Human relationships are as thin as paper; once rich one's face changes; this is the way of the world!” Angry, he left without saying goodbye. Returning home, he found a new house on his ruined land, greatly surprised how his young wife managed such renovation. Approaching the door, he found white papers pasted on either side — signifying mourning. Inside, his wife wore mourning clothes, crying bitterly before a coffin.
Lü Dongbin was stunned, wondering whose mourning she was in. Gently calling her “wife,” she turned in fear and asked, “Are you a man or a ghost?” More surprised, he asked why she said that. She looked carefully and then believed he had returned, exclaiming she was frightened to death, wondering if it was a dream.
It turned out that shortly after Lü Dongbin left, some people came to build a house for him and left. A few days earlier another group brought a coffin, claiming Lü Dongbin had died of cholera at Gou Yao’s home. His wife was devastated and cried uncontrollably. Today she cried, but Lü Dongbin unexpectedly returned.
Lü Dongbin understood it was a trick by Gou Yao. He grabbed a sharp axe and chopped open the coffin.

With a cracking sound, the coffin split open, revealing treasure and a letter. Lü Dongbin read: “Gou Yao is not an ungrateful man; he sent lots of silver to build the house. You had me guard an empty house; I made your wife weep bitterly.” Lü Dongbin smiled wryly, “Brother, your antics have truly troubled me!”
From then on, the two families grew closer. This is the story behind the saying, “Gou Yao and Lü Dongbin, not recognizing a kind heart,” because “Gou Yao” sounds like “dog bite,” and the story evolved into “Dog bites Lü Dongbin, not recognizing a kind heart.”
Dog Bite is actually a person’s name, and his name is Gou Yao