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:19:61 –

˹Therein are˺ gardens of perpetual residence which the Most Merciful has promised His servants in the unseen. Indeed, His promise has ever been coming.  

˹they shall enter˺ Gardens of Eden, as ˹a place of˺ residence (jannāti ‘Adnin, substitutes for al-janna, ‘Paradise’) which the Compassionate One has promised to His servants ˹a promise˺ in the Unseen (bi’lghaybi, a circumstantial qualifier, in other words ˹a promise made while˺ they do not see it). Indeed His promise, that is to say, that which He promises, is ever fulfilled, meaning that it always arrives (the original ˹form of ma’tiyyan˺ is ma’tūyun); or ˹what is meant by˺ His promise here is Paradise, to which those deserving of it shall arrive.
القرآن:١٩:٦١ –

جَنَّاتِ عَدْنٍ الَّتِي وَعَدَ الرَّحْمَٰنُ عِبَادَهُ بِالْغَيْبِ ۚ إِنَّهُ كَانَ وَعْدُهُ مَأْتِيًّا  

{جنات عدن} إقامة بدل من الجنة {التي وعد الرحمن عباده بالغيب} حال، أي غائبين عنها {إنه كان وعده} أي موعده {مأتيا} بمعنى آتيا وأصله مأتوي أو موعوده هنا الجنة يأتيه أهله.