﴿ ثُمَّ أَنزَلَ ٱللَّهُ سَكِينَتَهُۥ عَلَىٰ رَسُولِهِۦ وَعَلَى ٱلْمُؤْمِنِينَ وَأَنزَلَ جُنُودًۭا لَّمْ تَرَوْهَا وَعَذَّبَ ٱلَّذِينَ كَفَرُوا۟ ۚ وَذَٰلِكَ جَزَآءُ ٱلْكَٰفِرِينَ ﴾

“whereupon God bestowed from on high His [gift of] inner peace upon His Apostle and upon the believers, and bestowed [upon you] from on high forces which you could not see, and chastised those who were bent on denying the truth: for such is the recompense of all who deny the truth!”

(Then Allah sent His peace of reassurance) His tranquillity (down upon His messenger and upon the believers, and sent down hosts) from heaven (ye could not see) meaning angels, to assist the believers, (and punished those who disbelieved) through their killing and defeat. The reference here is to the clan of Malik Ibn 'Awf al-Dahmani, and to that of Kinanah Ibn 'Abd Yalayl al-Thaqafi. (Such is the reward of disbelievers) in the life of this world.