وَإِذْ يَعِدُكُمُ اللَّهُ إِحْدَى الطَّائِفَتَيْنِ أَنَّهَا لَكُمْ وَتَوَدُّونَ أَنَّ غَيْرَ ذَاتِ الشَّوْكَةِ تَكُونُ لَكُمْ وَيُرِيدُ اللَّهُ أَن يُحِقَّ الْحَقَّ بِكَلِمَاتِهِ وَيَقْطَعَ دَابِرَ الْكَافِرِينَ
“[Remember, O believers,] when Allah promised [to give] you the upper hand over either target, you wished to capture the unarmed party. But it was Allah's Will to establish the Truth by His Words and uproot the disbelievers.”
This ayah (Q8:7) recalls the same pre-battle moment -- the Muslims hoping for the weaker, unarmed caravan rather than Quraysh's army, when Allah had promised them victory over either.
Surah al-Anfal was revealed on the plains of Badr regarding the battle and its aftermath.
The lecture connects this promise's fulfillment of "the unarmed one" to the caravan captured in the Sariyya of Qarada.