Certainty in Allah's Promise

قُلْ هَلْ تَرَبَّصُونَ بِنَآ إِلَّآ إِحْدَى ٱلْحُسْنَيَيْنِ ۖ وَنَحْنُ نَتَرَبَّصُ بِكُمْ أَن يُصِيبَكُمُ ٱللَّهُ بِعَذَابٍ مِّنْ عِندِهِۦٓ أَوْ بِأَيْدِينَا ۖ فَتَرَبَّصُوٓا۟ إِنَّا مَعَكُم مُّتَرَبِّصُونَ

Say, "Do you await for us except one of the two best things [i.e., martyrdom or victory] while we await for you that Allāh will afflict you with punishment from Himself or at our hands? So wait; indeed we, along with you, are waiting."

وَيَقُولُونَ سُبْحَـٰنَ رَبِّنَآ إِن كَانَ وَعْدُ رَبِّنَا لَمَفْعُولًا

And they say, "Exalted is our Lord! Indeed, the promise of our Lord has been fulfilled."

فَٱصْبِرْ إِنَّ وَعْدَ ٱللَّهِ حَقٌّ ۖ وَلَا يَسْتَخِفَّنَّكَ ٱلَّذِينَ لَا يُوقِنُونَ

So be patient. Indeed, the promise of Allāh is truth. And let them not disquiet you who are not certain [in faith].

فَٱرْتَقِبْ يَوْمَ تَأْتِى ٱلسَّمَآءُ بِدُخَانٍ مُّبِينٍ

Then watch for the Day when the sky will bring a visible smoke

قُلْ تَرَبَّصُوا۟ فَإِنِّى مَعَكُم مِّنَ ٱلْمُتَرَبِّصِينَ

Say, "Wait, for indeed I am, with you, among the waiters."