Sahih Muslim 2955 a
Abu Huraira reported Allah's Messenger (ﷺ) as saying:
Between the two blowings of the trumpet (there would be an interval of forty). They said: Abu Huraira, do you mean forty days? He said: I cannot say anything. They said: Do you mean forty months? He said: I cannot say anything. They said: Do you mean forty years? He said: I cannot say anything. Then Allah would cause the water to, descend from the sky and they (people) will sprout like vegetable. The only thing in a man which would not decay would be one bone (the tailbone) from which the whole frame would be reconstituted on the Day of Resurrection.
حَدَّثَنَا أَبُو كُرَيْبٍ، مُحَمَّدُ بْنُ الْعَلاَءِ حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ أَبِي صَالِحٍ،
 عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ مَا بَيْنَ النَّفْخَتَيْنِ أَرْبَعُونَ
 ‏"‏ ‏.‏ قَالُوا يَا أَبَا هُرَيْرَةَ أَرْبَعُونَ يَوْمًا قَالَ أَبَيْتُ ‏.‏ قَالُوا أَرْبَعُونَ شَهْرًا قَالَ أَبَيْتُ ‏.‏ قَالُوا
 أَرْبَعُونَ سَنَةً قَالَ أَبَيْتُ ‏"‏ ثُمَّ يُنْزِلُ اللَّهُ مِنَ السَّمَاءِ مَاءً فَيَنْبُتُونَ كَمَا يَنْبُتُ الْبَقْلُ ‏"‏ ‏.‏ قَالَ
 ‏"‏ وَلَيْسَ مِنَ الإِنْسَانِ شَىْءٌ إِلاَّ يَبْلَى إِلاَّ عَظْمًا وَاحِدًا وَهُوَ عَجْبُ الذَّنَبِ وَمِنْهُ يُرَكَّبُ الْخَلْقُ
 يَوْمَ الْقِيَامَةِ ‏"‏ ‏.‏