وَلَقَدْ كَانُوا عَاهَدُوا اللَّهَ مِنْ قَبْلُ لَا يُوَلُّونَ الْأَدْبَارَ ۚ وَكَانَ عَهْدُ اللَّهِ مَسْئُولًا

Surah Al-Ahzab : 15
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.

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