It was recorded in the Two Sahihs that Abu Dharr swore that this Ayah --

﴿هَـذَانِ خَصْمَانِ اخْتَصَمُواْ فِى رَبِّهِمْ﴾

(These two opponents dispute with each other about their Lord;) was revealed concerning Hamzah and his two companions, and `Utbah and his two companions, on the day of Badr when they came forward to engage in single combat. This is the wording of Al-Bukhari in his Tafsir of this Ayah. Then Al-Bukhari recorded that `Ali bin Abi Talib said, "I will be the first one to kneel down before the Most Merciful so that the dispute may be settled on the Day of Resurrection.'' Qays (sub-narrator) said, "Concerning them the Ayah was revealed:

﴿هَـذَانِ خَصْمَانِ اخْتَصَمُواْ فِى رَبِّهِمْ﴾

(These two opponents dispute with each other about their Lord;) He (Qays) said, "They are the ones who came forward (for single combat) on the day of Badr: `Ali, Hamzah and `Ubaydah vs., Shaybah bin Rabi`ah, `Utbah bin Rabi`ah and Al-Walid bin `Utbah.'' This was reported only by Al-Bukhari. Ibn Abi Najih reported that Mujahid commented on this Ayah, "Such as the disbeliever and the believer disputing about the Resurrection.'' According to one report Mujahid and `Ata' commented on this Ayah, "This refers to the believers and the disbelievers.'' The view of Mujahid and `Ata' that this refers to the disbelievers and the believers, includes all opinions, the story of Badr as well as the others. For the believers want to support the religion of Allah, while the disbelievers want to extinguish the light of faith and to defeat the truth and cause falsehood to prevail. This was the view favored by Ibn Jarir, and it is good.