Praise be to Allah.
There is no proven Hadith which indicates that the Mahdi will be 52 years old when he appears; in fact, there is no proven report which says how old the Mahdi will be when he appears.
With regard to the Hadith in which it says that the Mahdi will be sent when he is forty years old, it is inauthentic and cannot be taken as evidence.
That is the Hadith which was narrated by At-Tabarani in Al-Mu`jam Al-Kabir (8/101) and in Musnad Ash-Shamiyyin (2/410) from Sulayman ibn Habib, who said: I heard Abu Umamah say: The Messenger of Allah (blessings and peace of Allah be upon him) said: “Between you and the Byzantines there will be four truces, the fourth of which will be concluded by a man from the family of Heraclius, which will last for seven years. A man from the tribe of `Abd Al-Qays whose name was Al-Mustawrid ibn Khilan said to him: O Messenger of Allah, who will be the leader of the people at that time? He said: “A forty-year-old man with a face like a shining star, on whose right cheek will be a black mole, and he will be wearing two white velvet `Abayahs, as if he is one of the Children of Israel. He will rule for twenty years and bring forth treasures, and will conquer the cities of the polytheists.”
This is a weak Hadith that cannot be quoted as evidence. Its chain of narration includes `Anbasah ibn Abi Saghirah, who is unknown.
Ibn Kathir said in Jami` Al-Masanid was-Sunan (8/528):
This Hadith was attributed to `Anbasah ibn Abi Saghirah, but his character and description are unknown. (End quote)
Al-Haythami (may Allah have mercy on him) said in Majma` az-Zawa’id (7/319):
It was narrated by At-Tabarani, and its chain of narration includes `Anbasah ibn Abi Saghirah, who is a weak narrator. End quote.
In Al-Fitan by Na`im ibn Hammad (1/365), it was narrated from Qatadah that `Abdullah ibn Al-Harith (may Allah be pleased with him) said: The Mahdi will appear when he is forty years old, looking like a man from among the Children of Israel.
This is a report which is not sound, because it was narrated by Al-Walid ibn Muslim, who narrated many reports that he did not hear directly from his Shaykh without mentioning the name of the third party from whom he heard it, or he attributed the report to the shaykh from whom he heard it, but referred to the Shaykh by a name or description that is not widely known [Tadlees]. He narrated this report by saying: ‘An [from], narrating it from Sa`id ibn `Abd Al-`Aziz from Qatadah.
In As-Sunan Al-Waridah fil-Fitan by Ad-Dani (5/1074), it says: From Qatadah, who said: It was said that the Mahdi will be forty years old, and he will do the deeds of the Children of Israel. If it is not ‘Umar, then I do not know who it will be.
Its chain of narration includes Abu Hilal Ar-Rasibi Al-Basri, who is a weak narrator.
Ahmad ibn Hanbal (may Allah have mercy on him) said: His Hadith is problematic.
Al-Bazzar (may Allah have mercy on him) said: He had a poor memory.
An-Nasa’i (may Allah have mercy on him) said: He is not strong in narration. (See: Tahdhib At-Tahdhib (9/196)
In conclusion, there is no sound Hadith or report which states how old the Mahdi will be when he appears.
Examine these answers for more context: (10301, 170174, 43840, 34890)
And Allah knows best.
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