Beliefs

The basis for the Shi'ah faith in Al-Mahdi (as) has reached us through successive narrations of the Holy Prophet (saws). Islam is the last true and Divine religion of Allah (swt), and we do not await any other religion to come and reform mankind. Oppression and corruption is spreading so much day by day and everywhere on this Earth, that there seems to be no hope of betterment. Unfortunately, even Muslims themselves have forsaken Islam's teachings and commandments. We find that as a result of the deteriorating condition of the Islamic countries the appearance of Al-Mahdi (as), the Savior, is necessary and we are awaiting him so that he may reform a humanity which has reached its lowest ebb and restore Islam to its lost glory. We also see that the Muslims are divided amongst each other, are involved in serious heresies and innovations, and are making changes in Islamic laws. The false claims of present and past generations of Muslims against each other are already on the surface, and it seems impossible that Islam may regain its strength and greatness under these conditions.

Under these circumstances only one person has the strength and power to revive the glory of Islam. The advent of this great reformer will unite the Muslims and through Divine Mercy will eradicate the evils, the perversions and the waywardness that has tarnished the image of Islam. Only such a reformer will possess the supermental power to bring about a revolution so that after the Earth is filled with oppression, justice will prevail upon it.

Humanity is in a terrible plight, oppression and corruption are prevalent everywhere and our belief that Islam is the true and the last Divine religion leads to the reappearance of such a great reformer as Al-Mahdi (as), the Savior, who will lead mankind to total salvation. We believe that the chain of Imams does not break at any time. It will continue uninterrupted on this Earth, although the Imam (as) may remain hidden until the time Allah (swt) wills that he should reappear.27

Concerning the second part of the question, Sunni Muslims believe that Al-Mahdi (as) is a Holy man who will appear before the Day of Judgement, and that he will be a descendant of the Prophet (saws) although he is not necessarily the son of Imam Hassan Al-'Askari (as). Muslims from all schools of thought unanimously agree on the coming of Al-Mahdi (as), but Sunnis are divided about his current status. According to some, he has yet to be born, others believe that he is born already. A few hold the opinion that he will come from the descendants of the Second Imam, Hassan al-Mujtabah (as), though their knowledge is fairly limited on this concept.28 But both Sunni and Shi'ah Muslims agree that Al-Mahdi (as) will appear as a religious and political leader to fill the Earth with justice and peace. In a hadith whose authenticity everyone agrees the Holy Prophet (saws) has said:

If there were to remain in the life of the world but one day, Allah would prolong that day until He sends in it a man from my community and may household. His name will be the same as my name. He will fill the Earth with justice and peace just as it is filled with oppression and tyranny.29

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27. Muzaffar, Muhammad Ridha, The Faith of Shi'a Islam. pp.70-73, Islamic Seminary Publications, 1985

28. Araki, Mohsin, Ideological and Jurisprudential Frontiers of Islam, p.20, Book Extra, London, 1999

29. Sunni references to this narration:

Sahih Tirmidhi 2:86, 9:74-75
Sunan Abu Dawud 2:7
Musnad Ahmad Ibn Hanbal 1:376 and 3:63
Mustadrak al-Sahihain al-Hakim 4:557
Al-Majma', Tabarani 217
Tahdhib al-Tahdhib, Ibn Hajar al-Asqalani, 9:144
Sawaiq al-Muhraqa, Ibn Hajar al-Haythami 167
Fathul Bari, Ibn Hajar al-Asqalani 7:305
Al-Tathkirah, al-Qutubi 617
Al-Hawi, al-Suyuti 2:65-166
Sharh al-Mawahib al-Ladunniyyah, al-Zurqani, 5:348
Fathul Mughith, al-Sakhawi 3:41
Al-Hafidh, Abul-Hassan Muhammad Ibn al-Husayn al-Sijistani al-Aburi
Al-Shafi'i (d. 363, 974) (Who said the above hadith is related by numerous authorities and was spread far and wide by many narrators and also in the works of Ibn Habban, Abu Nua'ym, Ibn Asakir, etc.

Adapted from the book: "The Awaited Saviour; Questions and Answers"