Bulugh al-Maram, Book 3, Hadith 618 (English)

‘Abdullah Ibn Ja’far (RAA) narrated, ‘When we received the news of Ja’far’s death; when he was killed (in the Battle of Mu’tah), the Prophet said: “Prepare some food for the family of Ja’far, for what has befallen them is keeping them preoccupied.” Related by the five lmams except for An-Nasa’i.

وَعَنْ عَبْدِ اَللَّهِ بْنِ جَعْفَرٍ رَضِيَ اَللَّهُ عَنْهُمَا قَالَ: { لَمَّا جَاءَ نَعْيُ جَعْفَرٍ ‏-حِينَ قُتِلَ‏- قَالَ اَلنَّبِيُّ ‏- صلى الله عليه وسلم ‏- "اصْنَعُوا لِآلِ جَعْفَرٍ طَعَامًا, فَقَدْ أَتَاهُمْ مَا يَشْغَلُهُمْ" } أَخْرَجَهُ الْخَمْسَةُ, إِلَّا النَّسَائِيّ َ 1‏.‏ ‏1 ‏- حسن.‏ رواه أحمد ( 1 / 205 )‏، وأبو داود ( 3132 )‏، والترمذي ( 998 )‏، وابن ماجه ( 1610 )‏، وقال الترمذي: "هذا حديث حسن صحيح".‏

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also referenced under: Book 3, Hadith 62 (In-Book)