﴿ وَلَقَدْ فَتَنَّا ٱلَّذِينَ مِن قَبْلِهِمْ ۖ فَلَيَعْلَمَنَّ ٱللَّهُ ٱلَّذِينَ صَدَقُوا۟ وَلَيَعْلَمَنَّ ٱلْكَٰذِبِينَ ﴾

“Yea, indeed, We did test those who lived before them; and so, [too, shall be tested the people now living: and] most certainly will God mark out those who prove themselves true, and most certainly will He mark out those who are lying.”

Please check ayah 29:4 for complete tafsir.