Abu Hurayrah (radiya Allahu anhu) narrated that the Messenger of Allah (salla Allahu alayhi wa sallam) said:
“The grave is more horrifying than any horrible scene I ever saw.”
[Tirmidhi, Bayhaqi, regarded as Hasan]
"Once you are carried to the graveyard you are brought close to the ground so that you dwell in a small, dark lonely hole. The nearest of kin and the most beloved to you will lower you into your grave, where you will rest placed on your right side, with the top of the shroud on your face untied and a stone placed on the hole (Lahd) inside your grave.
Then, soil is thrown into your grave and when the task is completed, one of the people will say, “Invoke Allah for forgiveness for your brother and for making him firm (so that he affirms to the angels Munkir and Nakir that Allah is his Lord, Islam is his religion and Muhammad is the Messenger he followed), for he is now being asked.”
[Silent Moments: The Description of Before and After Death Aspects by Abdul-Malik Al-Qasim]
Whenever Uthman (radiya Allahu anhu) stood next to a grave, he used to weep until his beard became wet. He was asked, “You mention Paradise and do not weep, but you weep from this scene?” He said, “The Messenger of Allah (sal Allahu alaihi wa sallam) said: “The grave is the first in the stages of the Hereafter. If one is saved from it, what is afterwards is even easier. If one is not saved from it, what comes after that is even harder.”
[Az-Zuhd, Page 189. Hasan hadith collected by Tirmidhi, Bayhaqi, Hakim.]
Imam Malik Ibn Anas saw the Death Angel in his sleep, and the Imam asked him: "How much left for me to live?" The Angel pointed to his five fingers. Then the Imam asked him: " Does that mean 5 years, or 5 months, or 5 days ?" Before the Imam had a chance to get an answer back, he woke up.
The Imam went to someone who would interpret dreams. That man told him: "Imam Malik, when the Angel pointed to his five fingers he didn't mean 5 years or months or days, but the Angel meant that your question 'how much left for me to live' is among 5 matters that only Allah (SWT) knows about, and he recited the following verse from the Qur,an:
" Verily, with ALLAH alone is the knowledge of the Hour. And HE sends down the rain, and HE knows what is in the wombs. And no soul knows what it will earn tomorrow, and no soul knows in what land it will die. Surely, ALLAH is All-Knowing, All-Aware." 31:34
Fear death, but do not hate it, prepare for it, but do not dread it.