Surah Al-Hijr — Ayah 4 (15:4)
وَمَآ أَهۡلَكۡنَا مِن قَرۡيَةٍ إِلَّا وَلَهَا كِتَابٞ مَّعۡلُومٞ ٤
English translation (Saheeh International)
And We did not destroy any city but that for it was a known decree.
Brief commentary
For each oppressive town that became destroyed, Allah already knew of its fixed time. The destruction will neither come before or after its time.