Surah Az-Zumar (The Successive Groups), Verse 54

وَاَنِیْبُوْۤا اِلٰی رَبِّكُمْ وَاَسْلِمُوْا لَهٗ مِنْ قَبْلِ اَنْ یَّاْتِیَكُمُ الْعَذَابُ ثُمَّ لَا تُنْصَرُوْنَ ۟

Wa aneebooo ilaa Rabbikum wa aslimoo lahoo min qabli any yaatiyakumul 'azaabu summa laa tunsaroon

“"Turn ye to our Lord (in repentance) and bow to His (Will), before the Penalty comes on you: after that ye shall not be helped.”

Quran 39:54 (Yusuf Ali Translation)