Gathering the Wrongdoers on the Day of Resurrection
Allah tells us about the Day of Resurrection when the wrongdoers who disbelieved in the signs and Messengers of Allah will be gathered before Allah, so that He will ask them about what they did in this world, rebuking, scolding and belittling them.
وَيَوْمَ نَحْشُرُ مِن كُلِّ أُمَّةٍ فَوْجاً
(And the Day when We shall gather out of every nation, a Fawj) means, from every people and generation a group
مِّمَّن يُكَذِّبُ بِـَايَـتِنَا
(of those who denied Our Ayat). This is like the Ayat:
احْشُرُواْ الَّذِينَ ظَلَمُواْ وَأَزْوَجَهُمْ
("Assemble those who did wrong, together with their companions (from the devils).") (37:22)
(and they will be kept under control - 27:83), The word used here is derived from Waz', which means to stop. The sense here is that the people in front will be stopped, so that those left behind could catch up. Some have taken the word Waz' in the sense of 'pushing'. Hence, it would mean that they would be pushed while being brought to their stand.
وَلَمْ تُحِيطُوا بِهَا عِلْمًا (while you did not comprehend them with knowledge - 27:84). There is an allusion in this verse that falsifying the message of Allah Ta` ala is by itself a great sin, especially when one falsifies it without giving any consideration or thought, then the crime is doubled. This has brought to light that if an issue or subject is duly considered and thought over, and yet one could not get to the truth, in that situation the intensity of the crime is reduced. Nevertheless, the denial of the existence of Allah and His Oneness would not save any one from infidelity and adoption of the wrong path, and would thus lead to perpetual torment. It is because they are such self-evident matters that any mistake of judgment is not allowed in them.
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 86–89
At the time when Almighty God takes the decision that the present history of the earth should be brought to an end, some extraordinary signs will appear to usher in the last phase. Among these signs will be the appearance of a communicator (dabbah). This will be the bell announcing the end of the examination period and not its beginning. Mass communications, particuarly the internet and multimedia, are probably what is meant by dabbah here. When all the people gather on the Day of Judgement, they will be divided into groups. The believers will be ranged on one side and those who denied the truth on the other. Then those who denied the truth will be asked what academic or rational arguments made them deny the Truth. At that time their silence will prove their denial was based on stubbornness and bias, though they advanced false arguments to show that they were right. At that time, it will be clear to them that over and above the verbal message of the preacher , even the alternation of day and night was non-verbally and tacitly conveying to them the words of Truth. Sleep during the night stood for death and waking up in the morning stood for resurrection. In spite of these extraordinary arrangements for the proclamation of the Truth, they were unable to discover it.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.