On the Day Earth is changed to other-than-Earth, and the heavens likewise, and they parade before Allah, the One, the All-Conquering. (Surah Ibrahim, 14:48)
Just as Allah relieves us of our sufferings and gives relief to our hearts, He has the power to punish us. The Qur'an gives examples of nations that He caused to perish at a time when they did not expect it—in the early morning—for they turned away from the just religion and rebelled against Allah. He sent them hurricanes that destroyed their houses and rained stones of hard baked clay upon them. To those whom He warned, He sent thunderstorms to raze their cities and sent earthquakes to turn the land upside down. Allah ruined them by sending a great blast. Allah's punishment is incomparable to any other punishment.
These are some of the punishment that Allah makes people taste in this world. But Hell's unprecedented torments deserve more consideration. Those who fail to appreciate Allah's power and who remain ungrateful, despite His infinite mercy, will be punished in the Hereafter.
When Allah casts the unbelievers into the midst of the Blazing Fire, they will encounter a form of misery previously unknown: Every time their skins are burned off, Allah will replace them and build walls of fire above them. The pain experienced in this world is utterly insignificant compared to the one in Hell. Indeed, the Qur'an informs us that the people of Hell will plead to Allah to kill them so that their pain will end. In Hell, Allah will punish unbelievers with His infinite power. This promise, which is certain to happen, is related in the following verses:
He is the Absolute Master over His servants. He is the All-Wise, the All-Aware. (Surat al-An‘am, 6:18)
Say: “Who is the Lord of the heavens and Earth?” Say: “Allah.” Say: “So why have you taken protectors apart from Him who possess no power to help or harm themselves?” Say: “Are the blind and seeing equal? Or are darkness and light the same? Or have they assigned partners to Allah who create as He creates, so that all creating seems the same to them?” Say: “Allah is the Creator of everything. He is the One, the All-Conquering.” (Surat ar-Ra‘d, 13:16)
The Day when they will issue forth and when not one thing about them will be hidden from Allah. “To whom does the kingdom belong today? To Allah, the One, the Conqueror!” (Surah Ghafir, 40:16)
Allah manifests His attribute of al-Qahhar upon those people who deny and refuse to believe in the Hereafter. However, Allah is infinitely compassionate and merciful toward His servants. After His servants' sincere repentance, Allah forgives their sins. He helps His sincere servants in both worlds and supports them with feelings of mercy, peace, and trust. In the Qur'an, Allah reveals His blessings upon believers and informs us that He does not punish His sincere servants, as follows:
Why should Allah punish you if you are thankful and believe? Allah is always responsive to gratitude, All-Knowing. (Surat an-Nisa', 4:147)