Quran 43:50 from Surah Az-Zukhruf on Divine Marvels.
فَلَمَّا كَشَفۡنَا عَنۡهُمُ ٱلۡعَذَابَ إِذَا هُمۡ يَنكُثُونَ
English translation: But when We removed from them the punishment behold! They broke (their word)
Transliteration: falamma kashafna anhumu al-'adhaba idha hum yankuthuna