The Prophet ﷺ said, "Between the two blowings of the trumpet there are forty."The people asked, "Abu Hurayrah, forty days?"He replied, "I cannot say."They asked, "Forty years?"He replied, "I cannot say."They asked, "Forty months?"He replied, "I cannot say. Every part of a person decays except the tailbone, from which creation will be reassembled."
عن النبي ﷺ قال: بين النفختين أربعون قالوا: يا أبا هريرة أربعون يوما؟ قال: أبيت، قال: أربعون سنة؟ قال: أبيت. قال: أربعون شهرا؟ قال: أبيت. ويبلى كل شيء من الإنسان إلا عجب ذنبه، فيه يركب الخلق.
Bukhari related it in tafsir (4814), and Muslim in Tribulations (2955), both from the hadith of Amash, who said, I heard Abu Salih say, I heard Abu Hurairah, and he narrated it. The wording given here is Bukhari's. Muslim added at the beginning of the hadith, "Then Allah will send down water from the sky, and they will sprout just as plants sprout, and there is nothing of the human being that does not decay except one bone, which is the tailbone."In another narration of his, from the hadith of Hammam bin Munabbih, "There is a bone in the human being that the earth never consumes, and on it he will be reassembled on the Day of Resurrection." They asked, "Which bone is that, O Messenger of Allah?" He said, "The tailbone."Bayhaqi said, "It seems that Abu Hurairah did not remember from the Prophet ﷺ what he meant by the forty, and the scholars of tafsir say it means forty years." Ithbat Azab Qabr (242).The hadith alludes to Allah's words, "And the Horn will be blown, and whoever is in the heavens and whoever is on the earth will fall dead, except whom Allah wills. Then it will be blown again, and at once they will be standing, looking on." [Zumar 39:68].They said that by Allah's words, "except whom Allah wills" [Zumar 39:68], is meant Jibreel, Mikail, Israfeel, and the angel of death. Then the angel of death is commanded to seize the soul of Mikail, then the soul of Jibreel, then the soul of Israfeel, and then the angel of death is commanded, and he dies. Then creation remains after the first blast in the intermediate realm for forty years. Then comes the second blast, and Allah brings Israfeel back to life and commands him to blow it. That is the meaning of Allah's words, "Then it will be blown again, and at once they will be standing, looking on." [Zumar 39:68], meaning standing on their feet, looking at the resurrection which they had denied in this world. Other explanations have also been given.They also said that the souls of the disbelievers used to be shown their abodes in the Fire morning and evening, and when the interval between the two blasts came, the punishment was lifted from them, so those souls slept between the two blasts. When they were raised at the second blast and witnessed on the Day of Resurrection what they had denied in this world concerning the resurrection and the reckoning, they cried out in woe, saying, "O woe to us, who has raised us up from our sleeping place?" [Yasin 36:52]. The angels said to them, "This is what the Merciful promised through the tongues of the messengers, that He would raise you after death, but you denied it, and the messengers spoke the truth that the resurrection is real."That was because, when the punishment was lifted from them for forty years, they thought that Allah would not punish them. But when the second blast was blown, "at once they will hasten from the graves to their Lord" [Yasin 36:51], they said, "O woe to us, who has raised us up from our sleeping place?" [Yasin 36:52], meaning, from our sleep.