In a previous entry, I mentioned the weakness of the Hadith used as the primary evidence for the false belief that the Prophets of God are bodily alive in their graves. My own belief, based on the Quraan and Sunna, is that the Prophets are not alive in their graves, rather they have died and their corpses mingled with dust; yes, their souls are living and residing blissfully in Janna with a peculiar spiritual life (not a bodily/worldly life). The Hadith in question:
الأَنْبِيَاءُ أَحْيَاءٌ فِي قُبُورِهِمْ يُصَلُّونَ
“The Prophets are alive in their graves, praying” is narrated in the collections of Abu Ya’la and al-Bazar. Note that it is not reported in the more authentic and well known collections of Hadith that form the Sihhah al-Sitta, or the six most authentic books of Hadith (Bukhari, Muslim, Tirmidhi, Abi Dawud, Nasa’i and Ibn Maja). In the previous entry regarding this Hadith and its content, I cited the contemporary Salafi muhaddith Zubair Ali Zai who weakened the Hadith based on the fact that the narrator al-Hajjaj is unknown. Although Ibn Hajr al-Asqalani authenticated this Hadith and posited the view that al-Hajjaj is in reality al-Hajjaj b. al-Aswad, this is actually speculation and therefore not sufficient to authenticate a Hadith dealing with such a delicate matter of creed.
Nevertheless, supposing, for the sake of argument, that the narrator in the Sanad of this Hadith is indeed al-Hajjaj b. al-Aswad, it should still be noted that Imam adh-Dhahabi (rahimahullah) weakened this Hadith explicitly and stated that the narrations of al-Hajjaj b. al-Aswad from Thabit al-Bunani are munkar (rejected).
Reference: Mizan-ul-I’tidal; v.1 p.460