The Pen
فَذَرْنِى وَمَن يُكَذِّبُ بِهَـٰذَا ٱلْحَدِيثِ ۖ سَنَسْتَدْرِجُهُم مِّنْ حَيْثُ لَا يَعْلَمُونَ
So leave Me, [O Muhammad], with [the matter of] whoever denies the Qur'an. We will progressively lead them [to punishment] from where they do not know.
Nearby ayahs help place verse 68:44 in sequence and meaning.
يَوْمَ يُكْشَفُ عَن سَاقٍ وَيُدْعَوْنَ إِلَى ٱلسُّجُودِ فَلَا يَسْتَطِيعُونَ
The Day the shin will be uncovered and they are invited to prostration but the disbelievers will not be able,
خَـٰشِعَةً أَبْصَـٰرُهُمْ تَرْهَقُهُمْ ذِلَّةٌ ۖ وَقَدْ كَانُوا۟ يُدْعَوْنَ إِلَى ٱلسُّجُودِ وَهُمْ سَـٰلِمُونَ
Their eyes humbled, humiliation will cover them. And they used to be invited to prostration while they were sound.
وَأُمْلِى لَهُمْ ۚ إِنَّ كَيْدِى مَتِينٌ
And I will give them time. Indeed, My plan is firm.
أَمْ تَسْـَٔلُهُمْ أَجْرًا فَهُم مِّن مَّغْرَمٍ مُّثْقَلُونَ
Or do you ask of them a payment, so they are by debt burdened down?