(They will remain) therein for ages, meaning: ages will pass upon them without ever coming to an end. A huqb (age) is eighty years, and the year is three hundred and sixty days, every day of which is a thousand years of the days of this world.
﴿لابثين فِيهَا أحقابا﴾ أَيْ: تَأْتِي عَلَيْهِمُ الأحقابُ لَا تَنْقَطِعُ أَبَدًا والحُقْبُ: ثَمَانُونَ عَامًا، والسَّنة: ثَلَاثمِائَة وَسِتُّونَ يَوْمًا، كُلُّ يَوْمٍ أَلْفُ يَوْم من أَيَّام الدُّنْيَا
