خَالِدِينَ فِيهَا مَا دَامَتِ السَّمَاوَاتُ وَالَارْضُ
They will dwell therein for all the time that the heavens and the earth endure,
Imam Abu Jafar bin Jarir said,
"It was from the customs of the Arabs that when they wanted to describe something that would last forever, they would say, `This is as enduring as the heavens and the earth.'
Or, `It will last as until the night and day separate.'
They would say, `As long as talkers at night continue to chat.' They meant by these statements the condition of eternity. Therefore, Allah addressed them in a manner that they were familiar with among themselves. Thus, He said,
خَالِدِينَ فِيهَا مَا دَامَتِ السَّمَاوَاتُ وَالَارْضُ
(They will dwell therein for all the time that the heavens and the earth endure).
The literal meaning is also intended with; "for all the time that the heavens and the earth endure."
This is due to the fact that there will be heavens and earth in the life of the next world, just as Allah said,
يَوْمَ تُبَدَّلُ الاٌّرْضُ غَيْرَ الاٌّرْضِ وَالسَّمَـوَتُ
On the Day when the earth will be changed to another earth and so will be the heavens. (14;48)
For this reason, Al-Hasan Al-Basri said concerning the statement of Allah,
مَا دَامَتِ السَّمَاوَاتُ وَالَارْضُ
(the heavens and the earth endure),
"Allah is referring to a heaven other than this heaven (which we see now) and an earth other than this earth. That (new) heaven and earth will be eternal."
Concerning Allah's statement,
إِلاَّ مَا شَاء رَبُّكَ
إِنَّ رَبَّكَ فَعَّالٌ لِّمَا يُرِيدُ
except as your Lord wills. Verily, your Lord is the doer of whatsoever He intends.
This is similar to His statement,
النَّارُ مَثْوَاكُمْ خَـلِدِينَ فِيهَأ إِلاَّ مَا شَأءَ اللَّهُ إِنَّ رَبَّكَ حَكِيمٌ عَلِيمٌ
The Fire be your dwelling place, you will dwell therein forever, except as Allah may will. Certainly your Lord is All-Wise, All-Knowing. (6;128)
It has been said that the exception mentioned in this verse refers to the disobedient among the people of Tawhid. It is these whom Allah will bring out of the Fire by the intercession of the interceders.
Those who will be allowed to intercede are the angels, the Prophets and the believers. They will intercede even on behalf of those who committed major sins. Then, the generous mercy of Allah will remove from the Fire those who have never done any good, except for saying La ilaha illallah one day of their life.
This has been mentioned in numerous authentic reports from the Messenger of Allah, including narrations from Anas bin Malik, Jabir bin Abdullah, Abu Sa`id Al-Khudri, Abu Hurayrah and other Companions.
No one remains in the Fire after this final intercession, except those who will remain there forever without escape. This is the opinion held by many of the scholars, both past and present, concerning the explanation of this verse