The Quran teaches that the present life is a trial in preparation for the next realm of our existence. A day will come when the whole universe will be destroyed and recreated, and the dead will be resurrected to stand in judgment before Allah:

One day the earth will be changed to a different earth, and so will be the heavens, and (men) will be marshalled forth, before Allah, the One, the Irresistible; (Quran 14:48)

The Day of Resurrection will be the beginning of another life, one that will be eternal. It is then that every person will be fully compensated by Allah for his or her good and evil deeds.

The explanation that the Quran gives about the necessity of life after death is exactly what the moral consciousness of man demands. If there were no life after death, the very belief in Allah would become meaningless, or even if one believed in Him, it would then be an unjust and indifferent deity, having once created man and no longer being concerned with his fate. Surely, Allah is just. He will punish the tyrants, whose crimes are beyond count – having killed hundreds of innocent people, created great corruption in society, enslaved numerous persons to serve their own whims, and so on. Because one has a short life span in this world and since numerous individuals are affected by one’s actions, adequate punishments and rewards are not possible in this life. The Quran very emphatically states that the Day of Judgment will come and that Allah will decide the fate of each soul.

Each and every human being longs for justice. Even if one does not uphold it for others they want justice for themselves. For example, tyrants and oppressors who are intoxicated by power and influence and inflict pain and suffering on others will object vehemently if any injustice is done to them. The reason such people become insensitive to the suffering of others is that they feel that power and influence prevents others from doing injustice to them.

Any person who has suffered injustice, irrespective of financial or social status, almost certainly wants its perpetrator to be punished. Though a large number of criminals are punished, many of them get off lightly or even scot-free. They may continue to lead pleasant, even luxurious lives and enjoy a peaceful existence. Allah may not punish a criminal in this world but He will surely hold him accountable on the Day of Judgment and punish him.