Abu ‘Abdur-Rahman Bilal bin Al-Harith Al-Muzani (RA) reported: The Messenger of Allah (peace be upon him) said, “A man speaks a good word without knowing its worth, Allah records for him His Good Pleasure till the day he will meet Him; and a man utters an evil word without realizing its importance, Allah records for him His displeasure till the day he will meet Him.”

(Riyad as-Salihin, Book 18, Hadith 1516)
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