Tafsir Al-Jalalayn: Hud, Ayah 107

(Abiding there) they will stay in the Fire forever (so long as the heavens and the earth endure) for as long as the heavens and the earth remain, from the moment they were created until the moment they lapse (save for that which thy Lord willeth) and your Lord has willed that they will abide in the Fire forever; it is also said: those who are damned will abide therein forever for as long as the heavens, the earth and the children of Adam subsist, except those whom Allah wills to change from damnation to felicity by His saying: (Allah effaceth what He will, and establishes [13:39]); it is also said that this means: they will abide in the Fire for as long as the heavens and the earth subsist: the heaven of the Fire and the earth of the Fire unless Allah wills to get the people who believed in Allah's divine Oneness out of it, those whose wretchedness was caused by a sin less than disbelief. Allah will enter these into Paradise because of their pure faith. (Lo! thy Lord is Doer of what He will) as He will.