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:54:8 –

Racing ahead toward the Caller. The disbelievers will say, "This is a difficult Day."  

scrambling, hastening with their necks stretched out, toward the Summoner. The disbelievers, among them, will say: ‘This is a hard day!’, a difficult one for disbelievers — as is stated in ˹sūrat˺ al-Muddaththir, a day of hardship for the disbelievers ˹Q. 74:9-10˺.
القرآن:٥٤:٨ –

مُهْطِعِينَ إِلَى الدَّاعِ ۖ يَقُولُ الْكَافِرُونَ هَٰذَا يَوْمٌ عَسِرٌ  

{مهطعين} مسرعين مادين أعناقهم {إلى الداعِ يقول الكافرون} منهم {هذا يوم عَسِرٌ} صعب على الكافرين كما في المدثر (يوم عسير على الكافرين).