(But nay, by thy Lord, they will not believe (in truth) until they make thee judge of what is in dispute between them…) [4:65].
This was revealed about al-Zubayr ibn al-'Awwam and his adversary Hatib ibn Abi Balta'ah, and it was also said that his adversary was Tha'labah ibn Hatib.
Abu Sa'id 'Abd al-Rahman ibn Hamdan informed us> Ahmad ibn Ja'far ibn Malik> 'Abd Allah ibn Ahmad ibn Hanbal> his father> Abu'l-Yaman> Shu'ayb> al-Zuhri> 'Urwah ibn al-Zubayr> his father that he used to relate that he once went to the Prophet, Allah bless him and give him peace, to settle a dispute he had with one of the Helpers who had participated in the Battle of Badr regarding a water conduit which they both used to water their land. The Prophet, Allah bless him and give him peace, said to al-Zubayr: “Water your land first and then let the water flow to your neighbour”. The Helper got angry and said: “O Messenger of Allah! You judged in this way because he is the son of your maternal aunt”. Upon hearing this, the face of the Messenger of Allah, Allah bless him and give him peace, flushed. He then said to al-Zubayr: “Water your land and then block the water until it goes back to its source”. In this way the Messenger of Allah, Allah bless him and give him peace, gave al-Zubayr his full right. His first command to al-Zubayr was made because he wanted to make it easy on both al-Zubayr and the Helper. But when the Helper protested against the judgement of the Messenger of Allah, he gave al-Zubayr his full right as he deserved this judgement in the first place.
Said 'Urwah: “By Allah, I do not think that this verse (But nay, by thy Lord, they will not believe (in truth) until they make thee judge of what is in dispute between them and find within themselves no dislike of that which thou decidest, and submit with full submission) was revealed about other than this incident”. This was narrated by Bukhari> 'Ali ibn 'Abd Allah> Muhammad ibn Ja'far> Ma'mar, and also by Muslim> Qutaybah> al-Layth and both al-Layth and Ma'mar related it from al-Zuhri.
Abu 'Abd al-Rahman ibn Abi Hamid informed us> Muhammad ibn 'Abd Allah ibn Muhammad al-Hafiz> Abu Ahmad Muhammad ibn Muhammad ibn al-Hasan al-Shaybani> Ahmad ibn Hammad ibn Zughbah> Hamid ibn Yahya ibn Hani' al-Balkhi> Sufyan> 'Amr ibn Dinar> Abu Salamah> Umm Salamah who related that al-Zubayr ibn al-'Awwam had a dispute with a man and the Messenger of Allah, Allah bless him and give him peace, judged in his favour. The man said that he judged in his favour because he was his cousin. And so Allah, exalted is He, revealed (But nay, by thy Lord, they will not believe…).
Asbab Al-Nuzul by Al-Wahidi , trans. Mokrane Guezzou