Surah Al-Ahzab 33:15

وَلَقَدْ كَانُوا۟ عَـٰهَدُوا۟ ٱللَّهَ مِن قَبْلُ لَا يُوَلُّونَ ٱلْأَدْبَـٰرَ ۚ وَكَانَ عَهْدُ ٱللَّهِ مَسْـُٔولًا

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.

Translation: Saheeh International

Tafsir

Though they had assuredly pledged to God before that that they would not turn their backs to flee; and a pledge given to God must be answered for regarding whether it was fulfilled or not.

Excerpt from Tafsir al-Jalalayn, commentary on 33:15, via Quran.com. The reader has the full commentary and 9 more tafsirs.