﴿ إِنَّآ أَخْلَصْنَٰهُم بِخَالِصَةٍۢ ذِكْرَى ٱلدَّارِ ﴾

“for, verily, We purified them by means of a thought most pure: the remembrance of the life to come.”

Assuredly We purified them with an exclusive thought namely the remembrance of the Abode of the Hereafter in other words to always remember it and to work for it a variant reading for bi-khālisatin dhikrā’l-dār has the genitive construction bi-khālisati dhikrā’l-dār making this dhikrā al-dār ‘remembrance of the Abode’ the explicative thereof.