Lu Jia, a native of Chu, served as an advisor to Emperor Gaozu of Han, accompanying him in the conquest of the realm. A sharp-tongued debater, he was always at the emperor's side and frequently dispatched as an envoy to the feudal lords.
One year, Emperor Gaozu sent Lu Jia to bestow upon Wei Tuo the seal and ribbon of the King of Nanyue. Though Wei Tuo was originally Chinese, he had long ruled as king in Nanyue and refused to help the realm overthrow the tyrants. Lu Jia urged him, "It would be wise to submit to the Han emperor soon, or you will bring ruin upon yourself."
Wei Tuo sprang up in alarm, knelt down, and apologized to Lu Jia, "Living long among the barbarians, I have lost all sense of propriety." Then he asked Lu Jia, "Compared to Xiao He, Cao Can, and Han Xin, which of them am I more worthy than?"
Lu Jia said, "You seem quite virtuous." Wei Tuo then asked, "Compared to the Han Emperor, who is more virtuous?"
Lu Jia replied, 'The Han Emperor rose from Feng and Pei to overthrow the brutal Qin, crushed the mighty Chu, and brought benefit to all under heaven by continuing the legacy of the Three Sovereigns and Five Emperors. China is vast, with fertile land and abundant resources, all united under one rule. But your Nanyue has no more than a few hundred thousand people, cramped in a territory no larger than a single Han commandery—how can you compare to the Han?' Wei Tuo, hearing these words, suddenly saw the light.
Wei Tuo was so delighted with Lu Jia that he kept him for months of drinking together. Wei Tuo said, "In Nanyue there is no one worth talking to, until you came and let me hear things I had never heard before."
Later, the idiom "never heard of before" came to be used to describe hearing something one has never heard before.
Source: *Records of the Grand Historian*, "Biographies of Li Yiji and Lu Jia"
Meaning of the Idiom: Later, the Chinese idiom "闻所未闻" came to describe hearing something one has never heard before.