وَلَقَد كانوا عاهَدُوا اللَّهَ مِن قَبلُ لا يُوَلّونَ الأَدبارَ ۚ وَكانَ عَهدُ اللَّهِ مَسئولًا

And they had already promised Allah before not to turn their backs and flee. And ever is the promise to Allah [that about which one will be] questioned.