The Prophet, sallallaahu alayhi wa sallam, receiving the news of his nation while in his grave
3-10-2006 | IslamWeb
Question:
What is the ruling on some people saying Prophet Muhammad, sallallaahu 'alayhi wa sallam, is Hayatun Nabi (not dead still alive)? Please explain with authentic references from the Hadeeth and Quran?
Answer:
All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
The Prophet 
is alive in his grave, a life of Barzakh (life in the grave after death); a life which only Allaah The Almighty knows about. We do not know anything about it except for the knowledge that we know from the texts that were revealed to us, and we believe in them as revealed or conveyed by the Messenger .
For instance, the Prophet said: "There is absolutely no one who sends his salutations upon me except that Allaah sends back my soul to me so that I would respond to his salutations." [Ahmad and Abu Daawood] When the Prophet informed the Companions 
that their salutations upon him are presented to him, they asked, "O Prophet of Allaah, how will our salutations upon you be presented to you when you are dead?" He replied: "Allaah has forbidden the earth to decompose the bodies of Prophets." [Abu Daawood, An-Nasaa'i and Ibn Maajah]
As regards the presenting of the deeds of his nation to him 'Abdullaah ibn Mas'ood 
narrated that the Prophet said: "Allaah has angels who travel across the land and they convey the greetings of my nation to me…My life is better for you as you would ask me and I would answer your queries, and my death is also good for you, your deeds are exposed to me, and the good that I see therein, I praise Allaah for that, and the evil that I see therein, I seek forgiveness of Allaah for you."
Al-Bazzaar 
commented on this narration saying, ''We do not know the ending of this narration, and it is only narrated from 'Abdullaah with this chain of narrators."
Indeed, some scholars 
classified the last portion of the narration as weak, like Al-Albaani while others classified it as authentic like Az-Zarqaani as he said, "It is reported by Al-Bazzaar with a good chain of narrators."
With regard to the affairs of the world being exposed to him, then we are not aware of any evidence proving this. In any case, no action or deed is dependent on knowing this issue.
For more benefit, please refer to Fatwa died and is buried in Madeenah">86435.
Allaah Knows best.