Imam Hasan Askari (a.s.) had informed about Mahdi (a.t.f.s.)
Imam Hasan Askari (a.s.) informed Moosa b. Ja’far Baghdadi,

‘It is as if I am seeing that you all are disputing about my successor. Beware! A Muslim may testify to all the Imams (a.s.) after the Holy Prophet (s.a.w.s.), but if he does not acknowledge my son’s Imamat, then he is just like that person who testifies to the prophethood of all prophets (a.s.) but rejects Prophet Muhammad (s.a.w.s.). Acknowledging our last is like acknowledging our first. Therefore, one who rejects the last has actually rejected (even) the first. Know that my son’s ghaybat will be so long that the people will be involved in doubts and uncertainties. Only those will be steadfast, whose faith is protected by Allah Himself.’

(Beharul Anwar vol 51, pg 160, Ithbatul Hidayah vol 6, pg 427)

In addition to the above tradition, there are 21 more traditions from Imam Hasan Askari (a.s.) in this regard.

Are traditions related to Mahdi (a.t.f.s.) authentic?

Engineer: Since you are able to identify the authentic and reliable reports, do you consider all traditions related to Mahdi (a.t.f.s.) as authentic?

Professor Nasir Mahdi: I cannot claim that all traditions related to Mahdi (a.t.f.s.) are authentic and that all the narrators are reliable and truthful. However, there is a group of traditions related to Mahdi that are deemed reliable.

Traditions related to Mahdi (a.t.f.s.) are authentic, reliable, good and also weak, just like traditions on other topics like prophethood, namaz, fasting, etc. However, this certainly does not mean that we scrutinise each and every tradition related to Mahdi and investigate each narrator in great depth to ascertain whether the tradition is authentic. You will see that there so many traditions related to Mahdi, that any unbiased and fair person will be satisfied with them.

Concept of a Messiah in other religions

Engineer: Is the concept of Mahdi restricted to Islam, or even other religions of the world have a similar belief and await such a universal reformer?

Professor Nasir Mahdi: The belief in Mahdi is by no means limited to Islam. Even other religions of the world share this belief. All these religions maintain that when injustice and oppression become commonplace and irreligiousness becomes the order of the day, a universal reformer shall emerge who shall rectify the situation with his extraordinary powers and miraculous capabilities. He shall establish the worship in one God as opposed to materialism. Glad tidings of such a reformer is found in the books of the Parsis, viz. Zand, Pazand and Jamasabnama. Divine religions like Judaism and Christianity also await such a reformer and their scriptures – Torah and Bible respectively, make ample mention of such a universal leader. In fact, even the Hindus and Buddhists advocate the emergence of such a reformer.

So we have seen that most religions believe in the rising of such a leader and are in fact awaiting his emergence. Every religion knows him with a different name. For instance, the Parsis identify him as ‘Sushyans’ (universal reformer), the Jews as ‘Sarware Israeli’, the Christians as ‘Promised Messiah’ and the Muslims as ‘Awaited Mahdi’. However every religion regards him in a distinct manner. For instance, the Jews believe that the universal reformer will tread on the path of Judaism. Similarly the Christians take the reformer to be one of them, while the Muslims believe that he will be from Bani Hashim and will be the son of the Prophet (s.a.w.s.). One noteworthy aspect about Islam is that the universal reformer is identified with distinctive traits and characteristics so that the people are able to recognise him when he emerges. However, this introduction is peculiar only to Islam and is missing in the other religions.

One thing worth noting about the Promised Mahdi in Islam (i.e. son of Imam Hasan Askari (a.s.)) is that he is the universal reformer even if we go by other religions. For instance, he is of Irani descent because Imam Sajjad (a.s.), the fourth Imam, was born of Janabe Shaharbanoo (s.a.), the daughter of the Persian king – Yazdjar. He is from Bani Hashim and Bani Israel. Both these tribes find their origin in Hazrat Ibrahim (a.s.) Khaleelullah. Bani Hashim is from the lineage of Hazrat Ismail (a.s.) Zabeehullah, the eldest son of Hazrat Ibrahim (a.s.). Bani Israel originates from Hazrat Izhaaq (a.s.) the younger son of Hazrat Ibrahim (a.s.). So both Bani Hashim and Bani Israel are in fact from the same lineage of Hazrat Ibrahim (a.s.).

Similarly it would not be wrong to say that the Mahdi is of Christian descent. This is because Imam Mahdi’s (a.t.f.s.) mother – Janabe Narjis Khatoon (s.a.) was the daughter of a Roman king. Details in this regard are available in several books.

It would not be right to limit the universal reformer to a particular race, nation or tribe. As all nations, tribes and races await his emergence, it would not be wrong to call him the Promised One of the World. Imam Mahdi (a.t.f.s.) will be the support and defendant of all worshippers of the One God. His victory will in fact be the triumph of all past prophets (a.s.) and all virtuous servants. He is the protector of Islam i.e. the religions of Hazrat Ibrahim (a.s.), Hazrat Moosa (a.s.), Hazrat Esa (a.s.). He will be the defendant of the true and original religions of Hazrat Moosa (a.s.) and Hazrat Esa (a.s.), in which there are glad tidings of the Holy Prophet’s (s.a.w.s.) advent.

By no means do we wish to establish the advent of the Promised Mahdi through the divine scriptures – Torah and Bible, nor do we feel necessary to do so. It is sufficient to say that all religions believe in the advent of an extraordinary personality who will establish universal peace and justice. All the past prophets (a.s.) have given glad tidings of his advent and the people of various nations are awaiting his reappearance.

Quran and the belief in Mahdi

Maula Abdul Ghani: If the belief in Mahdi was truly Islamic, mention of it would most certainly have been made in the Quran. However, let alone the belief, even the word Mahdi does not appear in the Quran.

Professor Nasir Mahdi: It is not true that every correct Islamic belief with all its traits and characteristics be found in the Quran. There are so many correct Islamic beliefs that are not mentioned at all in the Quran.

However there is adequate mention in the Quran of a day when the righteous and pious servants of Allah will be triumphant and successful and will inherit the earth. These worshippers in the One God will have complete power and authority over the world and Islam will finally reign supreme over all religions. For instance, it is narrated in Surae Ambiya:105,

‘And certainly We wrote in the Book after the reminder that (as for) the land, My righteous servants shall inherit it.’

Similarly in the 55th verse of Surae Nur it is mentioned,

‘Allah has promised to those of you who believe and do good that He will most certainly make them rulers in the earth as He made rulers those before them, and that He will most certainly establish for them their religion which He has chosen for them, and that He will most certainly, after their fear, give them security in exchange; they shall serve Me, not associating aught with Me; and whoever is ungrateful after this, these it is who are the transgressors.’

In Surae Qasas:4, Allah declares,

‘And We desired to bestow a favor upon those who were deemed weak in the land, and to make them the Imams, and to make them the heirs.’

In Surae Saff: 9, Allah reveals,

‘He it is Who sent His Apostle with the guidance and the true religion, that He may make it overcome the religions, all of them, though the polytheists may be averse.’

These are only a handful of Quranic verses that discuss about the Promised Mahdi – there are several more. All these verses announce a day when the righteous and pious believers shall dominate the world. These believers shall be the guides of all humanity and shall be the flag-bearers of the world’s civilisation and culture. Islam shall overcome all other religions. Tauheed shall replace apostasy. This bright and luminous day prophesied in the Quran is none other than the day of the Promised Mahdi’s advent. His revolution to establish peace and justice and destroy injustice and oppression will be achieved at the hands of pious believers. Inshallah.

(Quotes: WWW.Al Muntazar.net)