﴿ لَا يُقَٰتِلُونَكُمْ جَمِيعًا إِلَّا فِى قُرًۭى مُّحَصَّنَةٍ أَوْ مِن وَرَآءِ جُدُرٍۭ ۚ بَأْسُهُم بَيْنَهُمْ شَدِيدٌۭ ۚ تَحْسَبُهُمْ جَمِيعًۭا وَقُلُوبُهُمْ شَتَّىٰ ۚ ذَٰلِكَ بِأَنَّهُمْ قَوْمٌۭ لَّا يَعْقِلُونَ ﴾

“Never will they fight you, [even] in unison, otherwise than from within fortified strongholds or from behind walls. Severe is their warlike discord among themselves: thou wouldst think that they are united, whereas [in fact] their hearts are at odds [with one another]: this, because they are people who will not use their reason.”

Please check ayah 59:17 for complete tafsir.