The contemporary Scholar, Safi Golpaygani, has collected all these traditions in his book: Muntakhab al-athar, citing their Sunni and Shi'i sources. Following is the list of the subject and the number of traditions on that subject:
91 hadith on: "The Imams are twelve in number, among whom the first is 'Ali b. Abi Talib and the last is the Mahdi."
94 hadith on: "The Imams are twelve, and the last one is the Mahdi."
107 hadith on: "The Imams are twelve, nine among whom are the descendants of Husayn, and the ninth is the Qa'im."
389 hadith on: "Mahdi is from among the progeny of the Prophet."
214 hadith on: "Mahdi is from among the descendants of 'Ali."
192 hadith on: "Mahdi is from among the descendants of Fatima."
185 hadith on: "Mahdi is from among the descendants of Husayn."
148 hadith on: "Mahdi is the nineth descendant of Husayn."
185 hadith on: "Mahdi is among the descendants of 'Ali b. al-Husayn."
103 hadith on: "Mahdi is among the descendants of Imam Muhammad Baqir."
103 hadith on: "Mahdi is among the descendants of Imam Ja'far Sadiq."
99 hadith on: "Mahdi is the sixth descendant of Imam Sadiq."
101 hadith on: "Mahdi is among the descendants of Imam Musa al-Kazim."
98 hadith on: "Mahdi is the fifth descendant of Imam Kazim."
95 hadith on: "Mahdi is the fourth descendant of Imam 'Ali Rida."
90 hadith on: "Mahdi is the third descendant of Imam Muhammad Taqi."
90 hadith on: "Mahdi is among the descendants of Imam 'Ali al-Hadi."
145 hadith on: "Mahdi is Imam Hasan 'Askari's son."
148 hadith on: "The name of Mahdi's father is Hasan."
47 hadith on: "The name and patronymic of the Mahdi will be that of the Prophet's name and patronymic."1
The Prophet (peace be upon him and his progeny) declared:
The Promised Mahdi is among my descendants. His name and patronymic will be the same as mine. In creation and conduct he will be the closest to me. He will live a life of occultation during which people will become confused and lost. At that time, like a brilliant star he will appear and fill the earth with justice and equity, as it is filled with injustice and tyranny.2
As you can see from these hadith-reports, the Mahdi has been so clearly identified that there remains no doubt as to his identity. At this juncture, it seems appropriate to remind ourselves that on the basis of some of the prophetic traditions and historical reports one can surmise that the Prophet (peace be upon him and his progeny) had forbidden the combination of his name and patronymic in one person. Hence, this has been a rare occurrence in history.
In a hadith reported by Abu Hurayra the Prophet said: "Do not combine my name and my patronymic (kunya) in one person."3 It was because of this prohibition that when 'Ali b. Abi Talib chose the Prophet's name and patronymic for his son Muhammad b. Hanafiyya, the Prophet's companions objected to it. 'Ali b. Abi Talib in response to this objection said: "I have a special permission from the Prophet in this matter." A number of the companions confirmed 'Ali's statement.
If the content of this report is connected with the hadith-reports which relate that the Mahdi will have the Prophet's name and patronymic, then it becomes apparent that the Prophet wanted this combining of his name and patronymic to be part of the signs of the future Mahdi from which others were excluded. It was because of this coming together of the Prophet's name and patronymic in the case of Muhammad b. Hanafiyya that the latter referred to this fact as a sign of his own Mahdiism saying: "Yes, I am the Mahdi. My name is the Prophet's name; and my patronymic is his patronymic."4
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1 See: Lutf Allah al-Safi al-Gulpaygani, Muntakhab al-athar fi al-imam al-thani 'ashar (Tehran: Maktabat al-Sadr, nd.)
2 Majlisi, Bihar al-anwar, Volume 51, p. 72.
3 Ibn Sa'd, al-Tabaqat al-kubra, Vol. 1, p. 107.
4 Ibid., Vol. 5, p. 94.