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:31:9 –

Wherein they abide eternally; ˹it is˺ the promise of Allah ˹which is˺ truth. And He is the Exalted in Might, the Wise.  

abiding therein (khālidīna fīhā, is a circumstantial qualification ˹of a future status˺), in other words, their abiding therein will have been ordained once they enter it — a promise of God in truth, that is to say, God promised them this and realised it in truth; and He is the Mighty, Whom nothing can overwhelm and so prevent Him from fulfilling His promise and His threat ˹of chastisement˺, the Wise, the One Who assigns all things to their rightful places.
القرآن:٣١:٩ –

خَالِدِينَ فِيهَا ۖ وَعْدَ اللَّهِ حَقًّا ۚ وَهُوَ الْعَزِيزُ الْحَكِيمُ  

{خالدين فيها} حال مقدرة أي: مقدرا خلودهم فيها إذا دخلوها {وعد الله حقا} أي وعدهم الله ذلك وحقه حقا {وهو العزيز} الذي لا يغلبه شيء فيمنعه من إنجاز وعده ووعيده {الحكيم} الذي لا يضع شيئا إلا في محله.