Surah Az-Zumar 39:20

لَـٰكِنِ ٱلَّذِينَ ٱتَّقَوْا۟ رَبَّهُمْ لَهُمْ غُرَفٌ مِّن فَوْقِهَا غُرَفٌ مَّبْنِيَّةٌ تَجْرِى مِن تَحْتِهَا ٱلْأَنْهَـٰرُ ۖ وَعْدَ ٱللَّهِ ۖ لَا يُخْلِفُ ٱللَّهُ ٱلْمِيعَادَ

But those who have feared their Lord - for them are chambers, above them chambers built high, beneath which rivers flow. [This is] the promise of Allāh. Allāh does not fail in [His] promise.

Translation: Saheeh International

Tafsir

But as for those who fear their Lord and therefore obey Him — for them there will be lofty abodes with other lofty abodes built above them with rivers flowing beneath them that is beneath both the upper and the lower abodes — a promise of God wa‘da’Llāhi in the accusative because of an implied verb governing it. …

Excerpt from Tafsir al-Jalalayn, commentary on 39:20, via Quran.com. The reader has the full commentary and 9 more tafsirs.