Q 108: What is the textual proof from the Glorious Qur'an that the trial of the grave and its blessing or torment is a truth?
A--- Allah the Almighty says: {No! It is but a word that he speak; and behind them is Barzakh (a barrier) until the Day when they will be resurrected}. (Al-Mu'minun, 100)
Allah the Almighty says: {So Allah saved him from the evils that hey plotted (against him), while an evil torment encompassed Fir`aun's (Pharaoh) people. The Fire, they are exposed to it ,morning and afternoon. And on the Day when the Hour will be established (it will be said to the angels): "Cause Fir`aun's (Pharaoh) people to enter the severest torment!"}. (Ghafir, 45, 46)
Allah the Almighty says: {Allah will keep firm those who believe, with the word that stands firm in this world (i.e. they will keep on worshipping Allah Alone and none else), and in the Hereafter.24 }.
Allah the Almighty says: {And if you could but see when the Zalimun (polytheists and wrong-doers) are in the agonies of death, while the angels are stretching forth their hands (saying): Deliver your souls! Thisday you shall be recompensed with the torment of degradation because of what you used to utter against Allah other than the truth}. (Al-An' am, 93)
Allah the Almighty says: {We shall punish them twice, and thereafter they shall be brought back to a great (horrible)
torment}. (At-Taubah, 101)
Reference: 200 FAQ On Muslims Belief - Shiekh Hafiz Ibn Ahmed Al Hakami