Abu Dawud

Benefits and Issues:
➊
In reality, none of the Companions of the Prophet (sahabah) lived beyond a century; all of them had passed away.
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Therefore, after that, anyone claiming to be a Companion is making a completely false claim, just as it is mentioned regarding Ratan Hindi, who claimed to be a Companion five hundred years later.

➋
In light of this hadith, it is also argued regarding Khidr (alayhis salam) that he too has passed away. However, in contrast, others say that at that time he was not present on the earth, because there is no authentic evidence for the life of Khidr.

Explanation:
The last Companion to pass away was Abu al-Tufayl Amir bin Wathilah radi Allahu anhu. He passed away in 110 AH, that is, exactly one hundred years after the prophecy of the Prophet sallallahu alayhi wa sallam. Some people, upon hearing this hadith, thought that the Day of Judgment would occur after one hundred years. However, this was not the intent of the Prophetic hadith; rather, it simply meant that after one hundred years, a new generation would have come into existence and the present generation would have perished. The correspondence between the hadith and the chapter is evident.

Hadith Commentary:
Imam Bukhari rahimahullah’s sole purpose with this hadith is to clarify that scholarly discussions should not be considered as “nightly conversation after ‘Isha” (samar ba‘d al-‘isha) in the prohibited sense; rather, there is no harm in holding such gatherings. However, this does not mean that da‘wah assemblies should continue late into the night. Spending the entire night in gatherings of preaching and guidance is not a service to the religion.

Under this hadith also comes the issue of the life of Khidr, and thus it is established from this that he has departed from this world. A detailed discussion regarding this will be deferred to a later point.

And with Allah is success.

Explanation:
That is, within one hundred years, all the people who are alive today will have passed away, and new generations will continue to emerge. The last of the Companions (Sahabah) was Abu al-Tufayl ‘Amir ibn Wathilah, whose death occurred in 110 AH. Imam al-Bukhari rahimahullah has also used this hadith as evidence for the death of Khidr alayhis salam.

Hadith Commentary:
(1)
From this hadith, Imam Bukhari rahimahullah intends to establish that the term "‘atamah" can be used for ‘Isha, because it is authentically reported from the Messenger of Allah sallallahu alayhi wa sallam, whereas using the term "‘Isha" for Maghrib is not correct, as this is not established from the Messenger of Allah sallallahu alayhi wa sallam.
There is a difference of opinion among the early scholars regarding calling ‘Isha "‘atamah."
Ibn ‘Umar radi Allahu anhu used to be displeased with those who called it ‘atamah, whereas from Abu Bakr as-Siddiq radi Allahu anhu, permissibility is reported.
Some scholars have considered this usage to be contrary to what is preferable, and this is the stronger opinion.
(Fath al-Bari: 2/60)
(2)
There is a prohibition reported from the Messenger of Allah sallallahu alayhi wa sallam regarding calling the ‘Isha prayer "‘atamah," while at other times this term has also been used for the ‘Isha prayer.
There are two ways to reconcile between these:
➊ The prohibition is not for being unlawful (tahrim), but for being disliked (tanzih), and using the word ‘atamah for ‘Isha is permissible.
➋ The word ‘atamah was used in front of those people who did not know the name ‘Isha and for whom it was not well known; that is, the use of ‘atamah for ‘Isha was not as a name, but for the purpose of clarification.
(Sharh al-Nawawi: 4/208)

Hadith Commentary: Benefits and Issues: From this hadith, the intention of the Messenger of Allah (sallallahu alayhi wa sallam) was that, among the earthly creation, those people who are alive tonight, after one hundred years none of them will remain alive. And this statement was made by him in the last month of his life, in the 11th year of Hijrah, and the last Companion to remain alive was Abu Tufayl (radi Allahu anhu). After him, none of your (the Prophet’s) companions remained alive. However, some people misunderstood from this hadith that the Day of Judgment would be established after one hundred years, and Ibn Umar (radi Allahu anhu) wanted to refute such people. Therefore, those who were born after that night are not included in the purview of this statement.