Allah Most High has granted superiority to the Prophets (Sallallahu alaihi wa sallam) over all other creation and has granted them special honor and perfection. He has made the Holy Prophet (Sallallahu alaihi wa sallam) the leader of all the Prophets and has culminated Prophethood on Him. It is accepted universally by all Muslims that the Prophets are alive in their graves. It is proven by the Holy Quran and the Hadith:
And it is not (at all lawful) for you that you cause inconvenience to the Holy Messenger of Allah (blessings and peace be upon him), nor is this (lawful) that you marry his (pure) wives after him, till the end of time. Surely, it is the most grievous sin in the sight of Allah. Surah Ahzaab (33:53)
In this verse of the Holy Quran, Almighty Allah has strictly prohibited the Ummah from marrying any of the wives of the Holy Prophet (Sallallahu alaihi wa sallam). It is not permissible for any person to marry any of the wives of the Holy Prophet (Sallallahu alaihi wa sallam)
It is axiomatic in the science of jurisprudence (Fiqh) that when a person dies, the bond of marriage is undone. After the Iddat (the mandatory period after death of husband or divorce), the woman is entitled to marry anyone. On the other hand, if the husband is alive, no one can marry his wife. The strict prohibition in the aforementioned verse of the Holy Quran is a clear proof after passing away, the Holy Prophet (Sallallahu alaihi wa sallam) is alive in the netherworld with distinctive grandeur. There are various Hadith about this:
There is a Hadith in Sunan Ibn Majah:
Translation: It is narrated on the authority of Hadhrat Abu Darda (May Allah be well pleased with him), he says: The Holy Prophet (Sallallahu alaihi wa sallam) said: Almighty Allah has prohibited the earth to disturb the bodies of the Holy Prophet (Sallallahu alaihi wa sallam). The Prophets of Allah are alive and receive sustenance. (Sunan Ibn Majah, Hadith No. 1706)
Supplications for the forgiveness of the Ummah
Hadhrat Abu Bakr Siddiq (May Allah be well pleased with him) narrated the utterance of the Holy Prophet (Sallallahu alaihi wa sallam) that Prophets (May peace be upon him) are laid to rest wherever they pass away. Thus, the blessed body of the Holy Prophet (Sallallahu alaihi wa sallam) was laid to rest in the room of Hadhrat ‘Aisha (May Allah be well pleased with her) where He had passed away. (Sunan Ibn Majah, Hadith No. 1696)
The final resting place of the Holy Prophet (Sallallahu alaihi wa sallam) was made like a grave. Hadhrat ‘Ali, Hadhrat Fadhal bin ‘Abbas and Qutham bin ‘Abbas (May Allah be well pleased with them) had the honor of entering the grave. Qutham bin ‘Abbas (May Allah be well pleased with them) says: I was the last one to see the blessed countenance of the Holy Prophet (Sallallahu alaihi wa sallam). I saw that His blessed lips were moving. When I put my ear to His lips, I heard that the Holy Prophet (Sallallahu alaihi wa sallam) was saying: Rabbee Ummatee Ummatee, meaning O my Lord! Forgive my Ummah, forgive my Ummah. (Madarij Un Nubuwwah Farsi, Vol. 2, Pg. No. 442)