Surah Az-Zumar — Ayah 20 (39:20)

English translation (Saheeh International)

But those who have feared their Lord - for them are chambers,¹ above them chambers built high, beneath which rivers flow. [This is] the promise of Allāh. Allāh does not fail in [His] promise.

1. - i.e., elevated rooms, dwellings or palaces.

Brief commentary

But those who are mindful of their Lord, by fulfilling His instructions and avoiding His prohibitions, they will have lofty dwellings, one above the other, underneath which rivers flow. Allah has made a firm promise of this to them and Allah does not break His promise. He is far above that.