It is narrated from Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: The earth consumes the entire body of a human except for the last part of the tailbone. Someone asked: What is its size? He (peace and blessings be upon him) said: Like a mustard seed; you will be resurrected from it.
Hadith Referenceالفتح الربانی / بيان قيام الساعة، النفخ فى الصور، وبعث الناس من قبورهم / 13068
Hadith Gradingمحدثین:صحیح
Hadith Takhrij«حديث حسن لغيره، أخرجه ابويعلي: 1382، وابن حبان: 3140، والحاكم: 4/ 609 ، (انظر مسند أحمد ترقيم الرسالة: 11230/3 ترقیم بيت الأفكار الدولية: 11250»
Brief Explanation
Benefits: … The entire bodies of some individuals also remain intact in the grave; in any case, every person's 'ajb al-dhanab (the tailbone) remains. Whether the rest of the body perishes or remains, it is from this that the human will be recreated.