Quran 39:54 from Surah Az-Zumar on Divine Marvels.
وَأَنِيبُوٓاْ إِلَىٰ رَبِّكُمۡ وَأَسۡلِمُواْ لَهُۥ مِن قَبۡلِ أَن يَأۡتِيَكُمُ ٱلۡعَذَابُ ثُمَّ لَا تُنصَرُونَ
English translation: And turn to your Lord and submit to Him before before [that] comes to you the punishment then not you will be helped
Transliteration: wa-anibu ila rabbikum wa-aslimu lahu min qabli an yatiyakumu al-'adhabu thumma la tunsaruna