Nasai

(1) The principle and rule regarding water that flows naturally is that the first right to use such water belongs to the one who reaches it first and whose land, etc., is at the beginning of its course. Such a person has the complete right to irrigate his land, crops, and orchards fully. However, it is necessary for him that once his need is fulfilled, he should then let the water flow for the people downstream. The first person absolutely does not have the right to withhold this water.

(2) The ruler has the authority that if he deems it appropriate, he may mediate between the disputing parties and bring about reconciliation by finding a middle path. If the parties are not satisfied with this, then he should make a definitive judgment and grant each party its full right.

(3) This Companion was an Ansari and a participant of Badr, and it is established from the texts of the Qur’an and Hadith that the Companions who participated in Badr are certainly believers and destined for Paradise. Therefore, the words uttered by the Ansari were not due to hypocrisy, but rather were spoken under the influence of temporary emotions. That is why, upon your final decision, he submitted and did not raise any objection. This itself is proof of his faith. Moreover, you did not give a final verdict at first, but rather advised reconciliation. When reconciliation did not succeed, you then gave a definitive judgment.

(4) The purpose of the chapter is to show that even in a state of anger, there is no possibility of error. The benefit of the previous hadith regarding this matter should also be kept in view.

Hadith Commentary:
As far as the principle and rule are concerned, the noble statement of the Prophet (sallallahu alayhi wa sallam) in favor of Zubair (radi Allahu anhu) was entirely based on justice.
However, the Ansari companion perceived an aspect of partiality in it, which was not correct. Upon this, the noble verse was revealed, and unconditional obedience to the Messenger (sallallahu alayhi wa sallam) was declared the foundation of faith.
This noble verse also refutes those rigid followers (muqallidīn jāmidīn) who give preference to their imams over authentic ahadith and, through various excuses and pretexts, delay the judgment of the Prophet (sallallahu alayhi wa sallam).
Shah Waliullah (rahimahullah), in Hujjatullah al-Baligha, Volume 1, pages 365–366, states:
“So if an authentic hadith of the infallible Messenger reaches us, the obedience of which Allah has made obligatory upon us, and the opinion of the mujtahid is contrary to it, and despite this, we abandon the authentic hadith and follow the conjecture and speculative opinion of the mujtahid, then who can be more unjust than us? And what excuse will we present when people are brought before Allah, Lord of the worlds?”
Elsewhere, Shah Waliullah (rahimahullah) has declared such blind following (taqlid) to be included in the meaning of the verse:
‘They have taken their scholars and monks as lords besides Allah’ (: al-Tawbah: 31).
(Hujjatullah al-Baligha)

Hadith Commentary:
(1)
There is no doubt that the initial instruction which the Messenger of Allah (sallallahu alayhi wa sallam) gave to Zubair (radi Allahu anhu) contained latitude and concession for both parties. However, when the Ansari misconstrued this concession, the Messenger of Allah (sallallahu alayhi wa sallam) then granted Zubair (radi Allahu anhu) his full right in accordance with principle and regulation.
In this noble verse, obedience to the Messenger of Allah (sallallahu alayhi wa sallam) has been made the foundation of faith.

(2)
The purpose of Imam Bukhari (rahimahullah) is that when a judge commands reconciliation between two parties, but one party is not wholeheartedly willing to accept it, then action must be taken according to principle, and judgment will be passed in accordance with the law, in which there will be no aspect of concession for anyone.
And Allah knows best.