Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:14:43 –

Racing ahead, their heads raised up, their glance does not come back to them, and their hearts are void.  

as they come hastening (muhti‘īna is a circumstantial qualifier) with their heads turned upwards, to the heaven, their gaze, their sight, returning not to them, and their hearts as air, devoid of any sense, because of their being terror-stricken.
القرآن:١٤:٤٣ –

مُهْطِعِينَ مُقْنِعِي رُءُوسِهِمْ لَا يَرْتَدُّ إِلَيْهِمْ طَرْفُهُمْ ۖ وَأَفْئِدَتُهُمْ هَوَاءٌ  

{مهطعين} مسرعين حال {مقنعي} رافعي {رءُوسهم} إلى السماء {لا يرتد إليهم طرفهم} بصرهم {وأفئدتهم} قلوبهم {هواء} خالية من العقل لفزعهم.