Sunan Abi Dawud, Hadith 4725

Abu Hurairah reported the Apostle of AllSah as saying: Every son of Adam will be devoured by the earth with the exception of the tail-bone from which he was created and from which he will be reconstituted.

حَدَّثَنَا الْقَعْنَبِيُّ، عَنْ مَالِكٍ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏:‏ ‏ "‏ كُلَّ ابْنِ آدَمَ تَأْكُلُ الأَرْضُ إِلاَّ عَجْبَ الذَّنَبِ، مِنْهُ خُلِقَ وَفِيهِ يُرَكَّبُ ‏" ‏ ‏.‏

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also referenced under: Hadith 4743 (DarusSalam)