The origin of the idiom "loyal advice is harsh to the ears"?

The classic is "Historical Records: Biography of the Marquis of Huaiyin". The full sentence is: Poison is bitter in the mouth and is good for the disease; honest advice is bad for the ears and good for the deeds.

[Original text] If you often hear words that are offensive to your ears, and if you always have things that tickle your heart, they are the stepping stone for your moral cultivation. If your words are pleasing to your ears and your heart is cheerful in everything, your life will be buried in poison. Come on.

〔Translation〕You often hear some unflattering advice in your ears, and you often think of some unpleasant things in your heart. This is the whetstone for cultivating moral character. If all you hear are happy words and all you encounter are triumphant things, it will be like soaking your life in poisonous wine.

〔Commentary〕 People often say, "Good medicine is bitter but good for the disease; honest words are unpleasant to the ears but good for action." Only by listening to different opinions and accepting opinions from others can we absorb good advice. Even if it is really objectionable advice, we must be open-minded and learn from the negative side. Being easy to get angry and speaking lightly is just a kind of impetuousness, which must be overcome with efforts.