Quran 29:3 from Surah Al-Ankaboot on Divine Marvels.
وَلَقَدۡ فَتَنَّا ٱلَّذِينَ مِن قَبۡلِهِمۡۖ فَلَيَعۡلَمَنَّ ٱللَّهُ ٱلَّذِينَ صَدَقُواْ وَلَيَعۡلَمَنَّ ٱلۡكَٰذِبِينَ
English translation: And indeed We tested those who (were) before them (were) before them And will surely make evident Allah those who (are) truthful and will surely make evident the liars
Transliteration: walaqad fatanna alladhina min qablihim falaya'lamanna al-lahu alladhina sadaqu walaya'lamanna al-kadhibina