Al-Adab Al-Mufrad, Book 24, Hadith 7 (In-Book)

The Prophet, may Allah bless him and grant him peace, said, "Do you know what calumny is?" They said, "No, Allah and His Messenger know best." He said, "Telling people what other people have said in order to create dissension between them."

وَقَالَ النَّبِيُّ صلى الله عليه وسلم‏:‏ أَتَدْرُونَ مَا الْعَضْهُ‏؟‏ قَالُوا‏:‏ اللَّهُ وَرَسُولُهُ أَعْلَمُ، قَالَ‏:‏ نَقْلُ الْحَدِيثِ مِنْ بَعْضِ النَّاسِ إِلَى بَعْضٍ، لِيُفْسِدُوا بَيْنَهُمْ‏.‏

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