Imam ‘Ali Naqi (as) said, “ My successor will be my son Hasan; but what will be your condition during the reign of Hasan’s successor”? Those who were present asked, “Why, what do you mean by that”?
Imam replied, “you will not have the chance to see him, later you will not be allowed to mention his name”. Then the Imam was asked as to how they should mention him. Imam replied, “ You may say that he is the last of Muhammad’s (infallible) descendants. “
Some people asked Imam Hasan al-Askari (as) , “ your forefathers have said that the earth would never be without knowing the sign of Allah (Hujjatullah) till Doomsday, and he who dies without knowing the Imam of his time will die the death of ignorance”. Imam replied, “ That was as true as the shining day.
They inquired as to who would be the Imam who would be the sign of the Mercy of God after his death, Imam replied, “ He will be my son, the namesake of the Holy Prophet (Muhammad Abul Qasim). He who died without knowing him will die the death of ignorance.
His absence will be so lengthy that the ignorant will wander puzzled and would surely stray from the Right Path. But the Righteous shall remain steadfast and pray for their Imam to appear within their life time”.
All these predictions were recorded since the time of the Holy Prophet who himself prophesied the advent of the Mahdi. (Read this Hadith in the story of the 5th Imam).
As in the above saying of Imam Husayn (as) that due to the excessive length of the concealment of the 12th Imam many believers will have doubts about his existence. Many will question the very longevity of his life and the usefulness of his presence as an Imam.
To the question of existence, we have seen above the many Verses from the Qur’an and Hadith of the Prophet and all the Eleven Imams. We have also read quotations from the Books of Ahlul Sunna wal Jama’a and many scholars and philosophers from the earliest times to the present.