Quran 43:89 from Surah Az-Zukhruf on Divine Marvels.
فَٱصۡفَحۡ عَنۡهُمۡ وَقُلۡ سَلَٰمٞۚ فَسَوۡفَ يَعۡلَمُونَ
English translation: So turn away from them and say Peace But soon they will know
Transliteration: fa-is'fah anhum waqul salamun fasawfa ya'lamuna