Quran 3:63 from Surah Aal-i-Imraan on Divine Marvels.
فَإِن تَوَلَّوۡاْ فَإِنَّ ٱللَّهَ عَلِيمُۢ بِٱلۡمُفۡسِدِينَ
English translation: And if they turn back then indeed Allah (is) All-Knowing of the corrupters
Transliteration: fa-in tawallaw fa-inna al-laha alimun bil-muf'sidina