﴿ وَلَوْ قَٰتَلَكُمُ ٱلَّذِينَ كَفَرُوا۟ لَوَلَّوُا۟ ٱلْأَدْبَٰرَ ثُمَّ لَا يَجِدُونَ وَلِيًّۭا وَلَا نَصِيرًۭا ﴾

“And [now,] if they who are bent on denying the truth should fight against you, they will indeed turn their backs [in flight], and will find none to protect them and none to bring them succour:”

And if those who disbelieve had fought you at al-Hudaybiyya they would have turned their backs to flee — then they would not have found any protector to guard them or helper.