Intro
1:He will be from the family of Last Prophet Pbuh,
2: His name will be same as prophet name,
3: He will rule for seven years,
4: will fill the earth with equity and justice as it has been filled with oppression and tyranny.
If you believe that mahdi has arrived then show me a man with these characteristic and he must be a muslim from last ummah he should not Kafir, murtad or dajjal…
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Summary

The following are the collection of Sahih (authentic) Hadith regarding Mahdi.

Hadhrat Abdullah bin Mas’ood razil Allah hu anhu reports from the Prophet ( salullahu alaih wassalam ) , who said:

The world will not come to pass until a man from among my family, whose name will be my name, rules over the Arabs.
(Tirmidhi Sahih, Vol. 9, P. 74; Abu Dawud, Sahih, Vol. 5, P. 207;
also narrated by Ali b. Abi Talib, Abu Sa’id, Umm Salma, Abu Hurayra)

The Prophet ( salullahu alaih wassalam ) said:

Allah will bring out from concealment al-Mahdi from my family and just before the day of Judgment; even if only one day were to remain in the life of the world, and he will spread on this earth justice and equity and will eradicate tyranny and oppression.
(Musnad Ahmad Ibn Hanbal, Vol. 1, P. 99)

Hadhrat Ali ( razil Allah hu anhu ) narrates that Rasulullah ( salullahu alaih wassalam ) said:

Even if only a day remains for Qiyamah to come, yet Allah will surely send a man from my family who will fill this world with such justice and fairness, just as it initially was filled with oppression.
(Abu Dawood)

Ali b. Abi Talib ( razil Allah hu anhu ) has related a tradition from the Prophet (salullahu alaih wassalam) who informed him:

The promised Mahdi will be among my family. God will make the provisions for his emergence within a single night.
(Ibn Majah, Sahih, Vol. 2, P. 519)

Hazrat Umme Salmah ( razil Allah hu anhu ) , Prophet’s wife, narrates that she heard the Prophet ( salullahu alaihe wassalam ) say:

The promised Mahdi will be among my progeny, among the descendants of Fatima.
(Abu Dawud, Sahih, Vol. 2, P. 207; Ibn Majah, Sahih, Vol. 2, P. 519)

Rasulullah ( salullahu alaihe wassalam ) announced:

The Mahdi will be of my family, of the descendants of Fatima (the Prophet’s daughter). (Sunan Ibn Majah, Vol. 2, Tradition No. 4086)

The Prophet ( salullahu alaihe wassalam ) taught:

Al-Mahdi is one of us, the members of the household (Ahlul-Bayt).
(Sunan Ibn Majah, Vol. 2, Tradition No. 4085)

Abu Sa’id al-Khudari ( razil Allah hu anhu ) narrated that the Prophet ( salullahu alaihe wassalam ) said:

Our Mahdi will have a broad forehead and a pointed (prominent) nose. He will fill the earth with justice as it is filled with injustice and tyranny. He will rule for seven years.
(Abu Dawud, Sahih, Vol. 2, p. 208; Fusul al-muhimma, p. 275)

Hadhrat Abu Saeed Khudri ( razil Allah hu anhu ) relates that Rasulullah ( salullahu alaihe wassalam ) said:

Al Mahdi will be from my progeny. His forehead will be broad and his nose will be high. He will fill the world with justice and fairness at a time when the world will be filled with oppression. He will rule for seven years.

Hadhrat Umme Salmah ( razil Allah hu anhu ) narrates that Rasulullah ( salullahu alaihe wassalam ) said:

After the death of a Ruler there will be some dispute between the people. At that time a citizen of Madina will flee (from Madina) and go to Makkah. While in Makkah, certain people will approach him between Hajrul Aswad and Maqaame Ibraheem, and forcefully pledge their allegiance to him.

Thereafter a huge army will proceed from Syria to attack him but when they will be at Baida, which is between Makkah and Madina, they will be swallowed into the ground.

On seeing this, the Abdaals of Shaam as well as large numbers of people from Iraq will come to him and pledge their allegiance to him. Then a person from the Quraish, whose uncle will be from the Bani Kalb tribe will send an army to attack him, only to be overpowered, by the will of Allah. This (defeated) army will be that of the Bani Kalb. Unfortunate indeed is he who does not receive a share from the booty of the Kalb. This person (Imam Mahdi) will distribute the spoils of war after the battle. He will lead the people according to the Sunnat and during his reign Islam will spread throughout the world. He will remain till seven years (since his emergence). He will pass away and the Muslims will perform his Janazah salaat.
(Abu Dawood)

The holy Prophet ( salullahu alaihe wassalam ) said:

A group of my Ummah will fight for the truth until near the day of judgment when Jesus, the son of Marry, will descend, and the leader of them will ask him to lead the prayer, but Jesus declines, saying: “No, Verily, among you Allah has made leaders for others and He has bestowed his bounty upon them.
(Sahih Muslim)

It is reported from Abu Hurayra ( razil Allah hu anhu ) that the Prophet ( salullahu alaihe wassalam ) said:

What will be your reaction when the son of Mary (Jesus) descends and your Imam is from among yourselves?
(Sahih Muslim, bab nuzul ‘isa, Vol. 2; Sahih Bukhari, kitab bad’ al-khalq wa nuzul ‘isa, Vol. 4)

The holy Prophet ( salullahu alaihe wassalam ) said:

What would be your situation if the Son of Mary (i.e. Jesus) descends upon you and your Imam is from among you?
(Bukhari, kitabul-Anbiya, Chapter Nuzul Isa bin Maryam)
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