It is narrated from Sayyiduna Ubayy ibn Ka'b (may Allah be pleased with him) that a man was attributed (with a relation of ignorance), so he interrupted his speech by cursing the man's father's private parts. The people said: O Ubayy! You were not one to speak badly? He said: Indeed, we have been commanded to do this.
Hadith Referenceالفتح الربانی / القسم الخامس: مسائل الترهيب من الكبائر وسائر المعاصي / 9738
Hadith Gradingمحدثین:صحیح
Hadith Takhrij«اسناده حسن، وھو حديث سابق ترقیم بيت الأفكار الدولية: 21537»