Thus the Almighty Allah says...
He replied: No, because the knowledge of Allah dominates the knowledge of those who fix the time. The Almighty Allah promised thirty nights to Prophet Musa (a.s.) and then increased ten nights; but neither Prophet Musa (a.s.) was aware of it nor Bani Israel. Thus when the time expired, they said that Prophet Musa (a.s.) has deceived us. And they began to worship the calf.
Hence when famine and deprivation increases and people begin to deny each other, you should expect the arrival of divine command day and night.” 10- Ghaibat Tusi: It is narrated from Fadhl bin Shazan from Muhammad bin Ali from Sadan bin Muslim from Abu Basir that he asked the Imam (a.s.): “Is there a fixed time for reappearance; so that we can sit quietly till that time?” He replied: “It was fixed; but you people publicized it and it was postponed.” 11- Ghaibat Tusi: It is narrated from Fadhl from Hasan bin Mahbub from Abu Hamza Thumali that he said: “I asked Imam Muhammad Baqir (a.s.): O son of Allah’s Messenger, Amirul Momineen (a.s.) used to say: There will be sedition till 70 A.H.
and after that there will be peace and prosperity; but 70 A.H. has passed and we are still in problems?” Imam Muhammad Baqir (a.s.) said: “O Thabit, it was initially fixed as 70 A.H. but meanwhile Imam Husain (a.s.) was martyred and the Almighty Allah postponed it to 140 A.H.