Bukhari

Hadith Commentary:
When Jubayr bin Mut'im (radi Allahu anhu) was taken captive among the prisoners of Badr and was detained near the Prophet’s Mosque, he heard the recitation of Surah at-Tur from the Messenger of Allah (sallallahu alayhi wa sallam) during the Maghrib prayer, and later, being affected by this, he became Muslim.
From this, the relevance of the hadith to the chapter becomes clear.
Mut'im bin 'Adi (radi Allahu anhu) had done a favor to the Messenger of Allah (sallallahu alayhi wa sallam).
When he (sallallahu alayhi wa sallam) returned from Ta’if, he entered under his protection.
Mut'im (radi Allahu anhu) had his four sons armed and stationed at the four corners of the Ka'bah for the Prophet’s protection.
When the Quraysh saw this scene, they became afraid and said, “We cannot break the protection of Mut'im.”
Some have said that Mut'im (radi Allahu anhu) was the one who had the pact annulled which the Quraysh had made against Banu Hashim and Banu Muttalib.
The incident of the martyrdom of Uthman (radi Allahu anhu) is a source of discord (fitnah) in Islam.
It occurred on a Friday, on the eighth of Dhu al-Hijjah.
Regarding this, the statement of Sa'id bin al-Musayyib, according to Allamah Dawudi, is clearly incorrect, as even after this discord, many of the Badri Companions were still alive.
Some have said that by the first discord, he meant the martyrdom of Husayn (radi Allahu anhu), and by the second, the discord of Harrah, in which Yazid’s army attacked Madinah.
By the third discord, the discord of the Azariqah is meant,
which occurred in Iraq.
Some have answered thus: Sa'id bin al-Musayyib’s intent is that from the first discord, i.e., the killing of Uthman (radi Allahu anhu), until the second discord, i.e., Harrah, no Badri Companion remained alive.
This is correct, because among the last of the Badri Companions, Sa'd bin Abi Waqqas (radi Allahu anhu) passed away, and he too had died before the incident of Harrah.
By the third discord, some have meant the martyrdom of Abdullah bin Zubayr (radi Allahu anhu).
The meaning of the final phrase is that this tribulation completely ended the existence of the Companions, after which no Companion remained in the world.

Hadith Commentary:
➊
When Jubayr bin Mut'im (radi Allahu anhu) was brought as a captive among the prisoners of Badr and detained near the Prophet’s Mosque in Madinah, he heard the recitation of the Messenger of Allah (sallallahu alayhi wa sallam) during the Maghrib prayer and was deeply affected by it. This recitation later became the cause for his acceptance of Islam.
(Sahih al-Bukhari, al-Jihad, Hadith: 3050.)
According to another narration, Jubayr bin Mut'im (radi Allahu anhu) said:
When the Messenger of Allah (sallallahu alayhi wa sallam) recited certain verses, my heart nearly flew out of fear. Those verses were:
﴿أَمْ خُلِقُوا مِنْ غَيْرِ شَيْءٍ أَمْ هُمُ الْخَالِقُونَ (35)
أَمْ خَلَقُوا السَّمَاوَاتِ وَالْأَرْضَ ۚ بَل لَّا يُوقِنُونَ (36)
أَمْ عِندَهُمْ خَزَائِنُ رَبِّكَ أَمْ هُمُ الْمُصَيْطِرُونَ﴾
“Were they created by nothing, or are they themselves the creators? Or did they create the heavens and the earth? Rather, they are not certain. Or do they possess the treasures of your Lord, or are they the controllers (of them)?” (al-Tur: 35-36 and Sahih al-Bukhari, al-Tafsir, Hadith: 4853)

➋
Regarding the sentiments expressed by the Messenger of Allah (sallallahu alayhi wa sallam) about Mut'im bin 'Adi, the reason given is that when the Messenger of Allah (sallallahu alayhi wa sallam) returned from Ta’if, he entered under the protection of Mut'im. Mut'im, to safeguard him, armed his four sons and stationed them at the corners of the Ka'bah, which frightened the Quraysh and prevented them from harming the Prophet. They said: “We cannot break the protection of Mut'im.” Furthermore, he played a significant role in ending the pact that the Quraysh had made against Banu Hashim and Banu Muttalib.
(Fath al-Bari: 7/404)

➌
The martyrdom of 'Uthman (radi Allahu anhu) is a tremendous tragedy. This martyrdom was without cause and was an act of oppression. He adopted a policy of non-violence and did not raise the sword against the rebels. Allah, the Exalted, took retribution for this when, in the battles of Jamal, Siffin, and Nahrawan, thousands of Muslims were killed, and in fact, most of the Badri Companions had already met their deaths. This does not mean that all the Badri Companions fell victim to this tribulation, but rather that their deaths began at that time and they soon passed away. Among the Badri Companions, the last to pass away was Sa'd bin Abi Waqqas (radi Allahu anhu), who died a few years before the incident of Harrah. The third tribulation completely ended the existence of the Companions (radi Allahu anhum ajma'in). After that, no Companion remained alive.
(Fath al-Bari: 7/405)