33:15
وَلَقَدْ كَانُوا۟ عَـٰهَدُوا۟ ٱللَّهَ مِن قَبْلُ لَا يُوَلُّونَ ٱلْأَدْبَـٰرَ ۚ وَكَانَ عَهْدُ ٱللَّهِ مَسْـُٔولًا
walaqad kānū ʿāhadū l-laha min qablu lā yuwallūna l-adbāra wakāna ʿahdu l-lahi masūlan
Yet they had already promised God that they would not turn tail and flee, and a promise to God will be answered for.
And indeed they had already made a covenant with Allâh not to turn their backs, and a covenant with Allâh must be answered for.