(Al-Fath'h) 48 : 22
وَلَوْ قَاتَلَكُمُ الَّذِينَ كَفَرُوا لَوَلَّوُا الْأَدْبَارَ ثُمَّ لَا يَجِدُونَ وَلِيًّا وَلَا نَصِيرًا
And if those who disbelieved had been fighting against you, they would have turned in their backs, then they would find no protector, nor any helper.
See explanation 47: 25-26.