(Ali-Imran) 3 : 166
وَمَا أَصَابَكُمْ يَوْمَ الْتَقَى الْجَمْعَانِ فَبِإِذْنِ اللَّهِ وَلِيَعْلَمَ الْمُؤْمِنِينَ
And whatever happened to you on the day when both troops met, then it is with the Lord Allah’s Permission to know the believers.