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:73:18 –

The heaven will break apart therefrom; ever is His promise fulfilled.  

with the heaven being rent asunder thereon, on that Day, because of its severity. His promise, exalted be He, of the coming of that ˹Day˺, shall be fulfilled, that is to say, it will come to pass without doubt.
القرآن:٧٣:١٨ –

السَّمَاءُ مُنْفَطِرٌ بِهِ ۚ كَانَ وَعْدُهُ مَفْعُولًا  

{السماء منفطر} ذات انفطار، أي انشقاق {به} بذلك اليوم لشدته {كان وعده} تعالى بمجيء ذلك {مفعولا} أي هو كائن لا محالة.