﴿ بِسْمِ ٱللَّهِ ٱلرَّحْمَٰنِ ٱلرَّحِيمِ يَٰٓأَيُّهَا ٱلنَّاسُ ٱتَّقُوا۟ رَبَّكُمْ ۚ إِنَّ زَلْزَلَةَ ٱلسَّاعَةِ شَىْءٌ عَظِيمٌۭ ﴾

“O men! Be conscious of your Sustainer: for, verily the violent convulsion of the Last Hour will be an awesome thing!”

Please check ayah 22:2 for complete tafsir.