the author of basa'er-ud-darejat narrates from ali-ibn-esbaat as such: i saw hazrat abu jafar approaching towards me. when he came close to me i quickly cast my glance at him and looked at him from head to toe so that i could describe him to my friends in egypt. then he went into prostration and said: verily Allah has set forth argumentation in the matter of imamate just as he had done so in the case of prophethood and has said: ---
'and we granted him wisdom while yet a child.' also, he has said: ---
'until when he attains his maturity and reaches the age of forty.'
the author of 'yanabi-ul-muwadda' after mentioning the matter of Mahdi's birth, narrates on page 452 from the book 'fasl-ul-khetab' as such: 'about him, it has been said that the exalted Allah granted him wisdom, in his childhood and also made him a 'hujjat' (proof) for the people of the world. as, he says with regard to one of his prophets: ---
'o yahya! take hold of the book with strength, and we granted him wisdom while still a child.'
also, he says: ---
'they said: how should we speak to one who was a child in the cradle?
he said: surely i am the servant of Allah; he has given me the book and made me a prophet.'
ibn-hajar in his 'sawa'eq' (on page 114) after mentioning the incident of the demise of abu muhammad hassan askari writes:- 'he did not appoint anyone as his successor but abul-qasim muhammad hujjat whose age at the time of his father's demise was five years. however Allah granted him wisdom at that time.(82)
at the time of his father's demise he was five years old and Allah granted him wisdom in his very childhood just as he made prophet yahya as an imam in his infancy and appointed isa as a prophet in his childhood. also, shabrawi in al-ettehaf (on page 179) mentions his successorship to have started at the age of five after his father's demise and reckons his birth to have occurred in the night of 15th shaban. ibn-khallkan too (in wafiyat-ul-a'ayan vol. 1 pg. 451) has mentioned the birth of hazrat to be on the 15th shaban 255. suyediin 'saba'ek-uz-zahab' (page 78) has mentioned his age at the time of his father's demise to be five years.