Bulugh al-Maram, Book 3, Hadith 29 (In-Book)

‘Abdur Rahman bin Abi Laila (RAA) and ‘Zaid bin Arqam (RAA) used to recite four Takbirat when praying over the dead, but once he said it five times, so I asked him about it. He said to me, ‘The Messenger of Allah used to do so.’ Related by Muslim and the four Imams.

وَعَنْ عَبْدِ اَلرَّحْمَنِ بْنِ أَبِي لَيْلَى قَالَ: { كَانَ زَيْدُ بْنُ أَرْقَمَ يُكَبِّرُ عَلَى جَنَائِزِنَا أَرْبَعًا, وَإِنَّهُ كَبَّرَ عَلَى جَنَازَةٍ خَمْسًا, فَسَأَلْتُهُ فَقَالَ: كَانَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-يُكَبِّرُهَا } رَوَاهُ مُسْلِمٌ وَالْأَرْبَعَةُ 1‏.‏ ‏1 ‏- صحيح.‏ رواه مسلم (957)‏، وأبو داود (3197)‏، والنسائي (4/72)‏، والترمذي (1023)‏، وابن ماجه (1505)‏.‏

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also referenced under: Book 3, Hadith 585 (English)