Surah Az-Zumar (The Successive Groups), Verse 55

وَاتَّبِعُوْۤا اَحْسَنَ مَاۤ اُنْزِلَ اِلَیْكُمْ مِّنْ رَّبِّكُمْ مِّنْ قَبْلِ اَنْ یَّاْتِیَكُمُ الْعَذَابُ بَغْتَةً وَّاَنْتُمْ لَا تَشْعُرُوْنَ ۟

Wattabi'ooo ahsana maaa unzila ilaikum mir Rabbikum min qabli aiyaatiyakumal 'azaabu baghtatanw wa antum laa tash'uroon

“"And follow the best of (the courses) revealed to you from your Lord, before the Penalty comes on you - of a sudden while ye perceive not!-”

Quran 39:55 (Yusuf Ali Translation)