expression, godan verb (-u)
good advice is harsh to the ear
Proverb meaning that honest, well-intended advice often sounds unpleasant and is hard to accept.
忠言耳に逆らうというが、彼の厳しい言葉は本当にためになった。
They say good advice is harsh to the ear, but his stern words really helped me.
諫言 is a noun meaning 'admonition' or 'remonstrance', often used in formal contexts, while 忠言耳に逆らう is a full proverb expressing the difficulty of accepting good advice.
A similar proverb meaning 'good medicine tastes bitter', emphasizing that beneficial things are often unpleasant. 忠言耳に逆らう focuses specifically on advice.
A classical Chinese-derived proverb (故事成語). The exact origin is uncertain, but it reflects a common Confucian idea that loyal advice is often hard to hear.