Praise be to Allāh!
Three key questions will be asked in the grave:
- Who is your Lord?
- What is your religion?
- Who is this man (Prophet) who was sent among you?
Now, here’s something for you as reference to the above:
THE QUESTIONING OF THE BELIEVER
Al-Bara’ ibn ‘Azib reported: The Prophet, peace and blessings be upon him, said, “Verily, when the believer is ready to depart the world and is facing the Hereafter, angels from heaven descend with bright faces, as if their faces were the sun, with them are the shrouds and perfumes of Paradise, until they sit from him a distance as far as the eye can see. Then, the angel of death, upon him be peace, comes until he sits by his head and he says: O pure soul, come out to the forgiveness of Allah and His pleasure! He takes it out like a drop from a water-skin and holds it, never to leave his hand for the blink of an eye until he places it in that shroud and perfume. The scent coming from it is more pleasant than any musk you would find on the face of the earth. He ascends and passes by no gathering of angels but that they say: What a pure spirit! They say he is this person, son of this person, calling him by the best names by which he was known in the world, until he stops at the lowest heaven and seeks entry and it will be opened for him. The company of each heaven bring him closer to the heaven following it until he stops at the seventh heaven. Allah Almighty will say: Write the record of My servant in the righteous register and return him to the earth, for from it I created them, to it I return them, and from it I will take them out once again. His spirit will be returned to his body and two angels will come to sit by him, saying to him: Who is your Lord? He will say: My Lord is Allah. They will say: What is your religion? He will say: My religion is Islam. They will say: Who is this man sent you? He will say: He is the Messenger of Allah, peace and blessings be upon him. They will say: How did you know? He will say: I read the Book of Allah, had faith in it, and believed in it. A heavenly announcement will be made: My servant has spoken the truth! Spread out carpets for him in Paradise, clothe him for Paradise, and open a gate for him to Paradise! Its comforts and fragrances will come to him and his grave will become spacious as far as his eye can see. A handsome man, with fine clothes and wonderful fragrance, will come and say: Glad tidings of what pleases you, for this was your Day you were promised! He will say: Who are you with such a handsome face? He will say: I am your righteous deeds! He will say: O Lord, begin the Hour that I may return to my family and property!”
THE QUESTIONING OF THE DISBELIEVER
The Prophet ﷺ continued, “Verily, when the unbeliever is ready to depart the world and is facing the Hereafter, angels descend from heaven with darkened faces and with them sack-cloth. They will sit away from his as far as the eye can see. Then, the angel of death approaches until he sits by his head and he says: O filthy soul, come out to the displeasure of Allah and His wrath! He will be separated from his body like the tearing of skewers from wet wool and he holds it in his hand, never to leave it for the blink of an eye, until he places it in this sack-cloth. The scent coming from it is like the most foul corpse found upon the face of the earth. They will ascend with him and not pass by a gathering of angels but that they say: What a filthy spirit! They say he is this person, son of this person, calling him by the ugliest names by which he was known in the world, until he stops at the lowest heaven. They will request it to be opened for him but it will not open.” Then, the Prophet ﷺ recited the verse, “The gates of heaven will never open for them, nor will they enter Paradise, until the camel goes through the eye of the needle,” (7:40). The Prophet ﷺ said, “Allah Almighty will say: Write his record in the wicked register in the lowest earth. His spirit will be thrown down,” then the Prophet ﷺ recited the verse, “It is as though he had fallen from the sky and was snatched by the birds or the wind carried him down into a remote place,” (22:31). The Prophet ﷺ said, “His spirit will return to his body and two angels will come to sit by him, saying to him: Who is your Lord? He will say: Uh, uh, I do not know! They will say: What is your religion? He will say: Uh, uh, I do not know! They will say: Who is this man sent to you? He will say: Uh, uh, I do not know! A heavenly announcement will be made: He has lied! Spread carpets for him in Hellfire and open a gate for him to Hellfire! Its heat and its flames will approach him, and he will be squeezed in his grave until his ribs press together. An ugly man, with hideous clothing and a foul stench, will approach him and say: Glad tidings of what despairs you, for this is your Day you were promised! He will say: Who are with your evil face? He will say: I am your wicked deeds! He will say: O Lord, do not begin the Hour!” [Musnad Aḥmad 18534; Sahih (authentic) according to Al-Arna’ut]
Further,
The Messenger of Allah, peace and blessings be upon him, said, “It has been revealed to me that you will be put to trial in the grave, similar to the trial of the False Messiah. As for the believer or Muslim, he will say: Muhammad came to us with clear evidence and we answered him and believed in him. It will be said: Sleep in peace, for we knew you had conviction. As for the hypocrite or the doubter, he will say: I do not know, for I heard people saying something and I repeated it.” [Ṣaḥīḥ al-Bukhārī 7287]
And,
The Prophet, peace and blessings be upon him, said, “When the servant is placed in his grave, his companions turn and leave until he hears the scuffing of their sandals. Two angels come to him and sit by his head, saying to him: What do you say about this man, Muhammad? He says: I testify that he is the servant of Allah and His Messenger. It will be said: Look at your seat in Hellfire, for Allah has replaced it with a seat in Paradise. He will see them both together. As for the unbeliever or hypocrite, he says: I do not know, as I only said what people said! It will be said: You did not know, nor did you recite! Then he will be struck between his two ears with an iron hammer and he will cry out such that whoever is near him will hear it except humans and jinn.” [Ṣaḥīḥ al-Bukhārī 1338, Ṣaḥīḥ Muslim 2870]
and Allāh Knows Best!