3 : 166
وَمَآ أَصَٰبَكُمۡ يَوۡمَ ٱلۡتَقَى ٱلۡجَمۡعَانِ فَبِإِذۡنِ ٱللَّهِ وَلِيَعۡلَمَ ٱلۡمُؤۡمِنِينَ
What you suffered on the day [of ’Uhud] when the two armies met was by Allah’s permission, so that He may distinguish the [true] believers,