Quran 2:14 from Surah Al-Baqara on Divine Marvels.
وَإِذَا لَقُواْ ٱلَّذِينَ ءَامَنُواْ قَالُوٓاْ ءَامَنَّا وَإِذَا خَلَوۡاْ إِلَىٰ شَيَٰطِينِهِمۡ قَالُوٓاْ إِنَّا مَعَكُمۡ إِنَّمَا نَحۡنُ مُسۡتَهۡزِءُونَ
English translation: And when they meet those who believe[d] they say We believe[d] But when they are alone with their evil ones they say Indeed, we (are) with you only we (are) mockers
Transliteration: wa-idha laqu alladhina amanu qalu amanna wa-idha khalaw ila shayatinihim qalu inna ma'akum innama nahnu mus'tahziuna