The Refutation against Whoever denies Life after Death
Allah rebukes those who deny the Resurrection and the Final Gathering.
قُتِلَ الإِنسَـنُ مَآ أَكْفَرَهُ
(Qutila mankind!) Ad-Dahhak reported from Ibn `Abbas that he said,
قُتِلَ الإِنسَـنُ
(Qutila mankind!) "May man be cursed." Abu Malik also made a similar statement. He said, "This refers to the rejecting type of man, due to his abundant denial without any supporting argument. Rather he denies simply because he thinks it is farfetched and because he lacks knowledge of it." Ibn Jurayj said,
مَآ أَكْفَرَهُ
(How ungrateful he is!) "This means none is worse in disbelief than he is." Qatadah said,
ثُمَّ أَمَاتَهُ فَأَقْبَرَهُ (Later, he made him die, and put him into the grave..80:21) After mentioning the inception of human life, Allah points to its end, that is, death and grave. Death has been mentioned here in the context of blessings of Allah. It indicates that death is a blessing rather than a calamity. The Holy Prophet ﷺ is reported to have put it thus: تحفَۃ المؤمِن الموت "The gift of a believer is death." Moreover, there is a profound wisdom in death at macro level for the entire world.
The phrase فَأَقْبَرَهُ fa-aqbarah (and put him into the grave) describes another blessing of Allah, in that when man is dead, he is not left lying on the earth like other animals where he might rot, blow up and burst [ and probably be ravaged by vultures or beasts ]. But, even after death, he is honoured in the most befitting manner. His body is washed ceremonially, enshrouded in clean cloths, and buried in a grave with respect.
This verse also indicates that it is obligatory to bury a dead human body.
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 20–23
The Prophet Muhammad was once preaching to the chiefs of the Quraysh in Makkah, when a blind man, ‘Abdullah ibn Umm al-Maktum, arrived at the gathering and said, ‘O, Prophet of God ! Please teach me something of what God has taught you.’ The arrival of a blind person at this juncture displeased the Prophet. These verses were revealed on that occasion. In these verses the apparent addressee is the Prophet Muhammad, but actually it has been clarified with reference to this incident that, in the eyes of God, those prominent people who have turned away from religion have no value. Before God, the valued person is the one who is imbued with the God-fearing spirit, though apparently he may be a ‘blind’ person.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.