Bukhari

Lexical Explanation:
«اِمَامُكُمْ مِنْكُمْ» "Your imam will be from among you," meaning that when Isa (alayhis salam) descends, he will not lead the prayer; rather, at that time, someone from among you who is present will lead the prayer. [كشف المشكل لا بن الجوزي 882/1، فيض القدير 74/5]

Hadith Commentary: There is consensus (ijma‘) of the Islamic Ummah on the descent of ‘Isa ibn Maryam (alayhis salam) from the heavens in the end times. The Qur’anic verse, “And there is none from the People of the Book...” (), is a definitive text (nass qat‘i) regarding this belief, and authentic ahadith (ahadith sahihah) are present on this matter.

In this end era, a few people of the “naturalist” (neechari) type have denied this belief, and a person from Punjab, Mirza Qadiani, greatly promoted this denial and made his false belief regarding the death of ‘Isa (alayhis salam) famous in opposition to all the Muslims of the past and present, which is manifestly false.

No steadfast believer should be affected by the nonsense of such people with corrupt beliefs.

Hadith Commentary:
➊
"Your imam will be from among you."
At the time of the descent of the Messiah (Isa, alayhis salam), it will be the time for prayer, and the congregation will be led by your imam, that is, Imam Mahdi, as narrated from Jabir bin Abdullah radi Allahu anhu that when Isa alayhis salam descends, the leader of the Muslims will say to him:
"Come, lead us in prayer."
He will reply:
"No, you are leaders over one another. Allah has honored this ummah with this distinction."
(Sahih Muslim, Kitab al-Iman, Hadith: 395(156))
It should be noted that the first prayer will be led by Imam Mahdi, and Sayyiduna Isa alayhis salam will pray behind him, but after that, the subsequent prayers will be led by Isa alayhis salam himself, as clarified in other ahadith.
The second meaning of this phrase is that Isa alayhis salam will be your caliph and will be upon your religion, and will judge according to the Qur'an, not act upon the Gospel (Injil).
However, the first meaning appears to be weightier.

➋
The manner of the descent of Isa alayhis salam will be that he will be wearing two light yellow garments, with his hands placed on the shoulders of two angels, descending near the white minaret in the east of Damascus.
When he lowers his head, drops like pearls will be seen falling, and when he raises his head, the same will be observed.
Any disbeliever who smells his breath will die, and his breath will reach as far as his sight extends. Then he will search for the Dajjal and find him at the gate of Ludd, and then he will kill him.
(Sahih Muslim, Kitab al-Fitan, Hadith: 7373(2937))
Abdullah bin Umar radi Allahu anhu narrates that the Messenger of Allah sallallahu alayhi wa sallam said:
"The Dajjal will emerge among my ummah and will remain for forty..."
The narrator says: I do not know whether he said forty days or forty years.
Then Allah will send Isa alayhis salam.
He will resemble Urwah bin Mas'ud radi Allahu anhu.
Isa alayhis salam will search for the Dajjal and kill him.
Then for seven years, people will live in such a way that there will be no enmity between any two persons."
(Sahih Muslim, Kitab al-Fitan, Hadith: 7381(2940))
In the narration of Nawwas bin Sam'an, it is stated that the Dajjal will remain in this world for forty days.
(Sahih Muslim, Kitab al-Fitan, Hadith: 7373(2937))
In any case, Isa alayhis salam was raised alive to the heavens.
He is alive in the heavens and will descend near the Day of Judgment, and after killing the Dajjal, he will establish the banner of the Book and the Sunnah on this earth.
The famous Tabi'i Hasan rahimahullah says:
By Allah! Isa is alive with Allah, but when he descends, all people will believe in him.
(Tafsir Tabari: 14/6)
The renowned Imam Abu al-Hasan al-Ash'ari rahimahullah says:
There is consensus of the ummah on the fact that Allah raised Isa alayhis salam towards the heavens.
(al-Ibanah 'an Usul al-Diyanah, p. 34)
After descending to the earth, Isa alayhis salam will remain for forty years as a just imam and fair ruler, and will judge according to the Shari'ah of Muhammad sallallahu alayhi wa sallam.
(Musnad Ahmad: 75/6)
When the Messenger of Allah sallallahu alayhi wa sallam was taken on the Mi'raj, he met Sayyiduna Ibrahim alayhis salam, Sayyiduna Musa alayhis salam, and Sayyiduna Isa alayhis salam, and they discussed the Hour (Qiyamah) among themselves.
Eventually, Isa alayhis salam was asked about the Hour, and he replied:
"It has been promised to me that I will descend before the Hour, but only Allah knows its time."
He mentioned the emergence of the Dajjal and said:
"I will descend and kill him."
(Sunan Ibn Majah, Kitab al-Fitan, Hadith: 4081; al-Mustadrak lil-Hakim: 384/2)
The Messenger of Allah sallallahu alayhi wa sallam mentioned ten signs before the Hour, among which is the descent of Isa alayhis salam.
(Sahih Muslim, Kitab al-Fitan, Hadith: 7285(2901))
The wisdom in the descent of Isa alayhis salam near the Day of Judgment is that it refutes the Jews who claimed that they killed him, so Allah will belie them in such a way that not only did they not kill Isa alayhis salam, but he himself will kill them (the Jews), and he will also manifest the falsity of the Christians' false claims.
And Allah knows best.