وَلَقَدْ فَتَنَّا الَّذِينَ مِنْ قَبْلِهِمْ ۖ فَلَيَعْلَمَنَّ اللَّهُ الَّذِينَ صَدَقُوا وَلَيَعْلَمَنَّ الْكَاذِبِينَ 3
We did test those before them, and Allah will certainly know those who are true from those who are false.