Whoever listens to the talk of some people while they dislike that, molten lead shall be poured into his ears on the Day of Judgment
Authentic hadithعن عبد الله بن عباس رضي الله عنهما أن رسول الله صلى الله عليه وسلم قال: «من تَسَمَّع حديث قوم وهم له كارهون؛ صُبَّ في أذنيه الآنُكُ يوم القيامة».
‘Abdullāh ibn ‘Abbās (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "Whoever listens to the talk of some people while they dislike that, molten lead shall be poured into his ears on the Day of Judgment."
Explanation
This Hadīth contains a severe warning to those who listen to the talk of others while they dislike that. Indeed, this is a bad manner amounting to a major sin. So, like fault, like punishment. Since a person commits this sin with his ears, he shall be punished in his ears: by the pouring of molten lead therein. This applies regardless of whether the talking people’s dislike is based on a valid reason or not. In fact, some people dislike that others should listen to their conversations even if they say nothing shameful, wrong, or unlawful. They just do not like to be heard by anyone.
Source · Al-Bukhari with a similar wording
From the Hadith Encyclopedia (hadeethenc.com).