Hadith: If a man says: People are ruined, he himself will be the most ruined among them all

عن أبي هريرة رضي الله عنه أن رسول الله صلى الله عليه وسلم قال: «إذا قال الرَّجُل: هَلَكَ الناس، فهو أَهْلَكُهُم».
[صحيح] - [رواه مسلم]

Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "If a man says: People are ruined, he himself will be the most ruined among them all."
[Authentic hadith] - [Narrated by Muslim]

Explanation

If a man says: "People are ruined" with the intention of degrading and belittling them and considering himself in a higher rank and better position than them, he shall be the most ruined among them. The wording of another narration reads: "...he man will ruin people." In this case, it means this man is a reason for their being ruined, because he causes them to despair and lose hope in the mercy of Allah. By doing so, he prevents them from returning to Allah in repentance and pushes them in the way of despair until they become ruined.