وَلَقَدْ كَانُوا۟ عَٰهَدُوا۟ ٱللَّهَ مِن قَبْلُ لَا يُوَلُّونَ ٱلْأَدْبَٰرَ ۚ وَكَانَ عَهْدُ ٱللَّهِ مَسْـُٔولًا

And certainly they had made a covenant with Allah before, that) they would not turn (their) backs; and Allah’s covenant shall be inquired of.