مُهْطِعِينَhastening forward,in a hurry.Allah said in other Ayat,مُّهْطِعِينَ إِلَى الدَّاعِHastening towards the caller. (54:8) يَوْمَيِذٍ يَتَّبِعُونَ الدَّاعِىَ لَا عِوَجَ لَهُOn that Day mankind will follow strictly Allah's caller, no crookedness will they show him.) (20:108) until, وَعَنَتِ الْوُجُوهُ لِلْحَىِّ الْقَيُّومِAnd (all) faces shall be humbled before the Ever Living, the Sustainer. (20:111)Allah said:another Ayah,يَوْمَ يَخْرُجُونَ مِنَ الاٌّجْدَاثِ سِرَاعاًThe Day when they will come out of the graves quickly. (70:43)Allah said next,مُقْنِعِي رُءُوسِهِمْwith necks outstretched,meaning, raising their heads up, according to Ibn Abbas, Mujahid and several others.Allah said next,لَا يَرْتَدُّ إِلَيْهِمْ طَرْفُهُمْtheir gaze returning not towards them,meaning, their eyes are staring in confusion, trying not to blink because of the horror and tremendous insights they are experiencing, and fear of what is going to strike them, we seek refuge with Allah from this end.This is why Allah said,وَأَفْيِدَتُهُمْ هَوَاءand their hearts empty.meaning, their hearts are empty due to extreme fear and fright.Qatadah and several others said that;the places of their hearts are empty then, because the hearts will ascend to the throats due to extreme fear