Al-Ahzab 33:15

Walaqad kanoo AAahadoo Allahamin qablu la yuwalloona al-adbara wakanaAAahdu Allahi mas-oola

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

despite that they had already made a covenant with Allah that they would not turn their backs; and a covenant with Allah has to be answered for.