It is mentioned in Musnad of Ahmad Ibn Hanbal, vol. 1, p. 376 and Sunan al-Tirmidhi, vol. 4, Book 34, Chapter 52, p. 505, H. 2231 that Abdullah Ibn Masood narrates from the Holy Prophet (s.a.w.a.) who informed:
“The Day of Resurrection will not occur until a person from my Ahlul Bait whose name will be the same as my name does not rise.”
Apart from this, the Ahle Tasannun scholar Ibrahim Hamveeni in his book Faraaed al-Simtain, vol. 2, pp. 325-326, H. 575 narrates from the great companion Huzaifah al-Yamaani (a.r.) that:
One day the Holy Prophet (peace be upon him and his holy progeny) was delivering a sermon in which he was mentioning the events of the future when he (peace be upon him and his holy progeny) said,
“Even if there remains only one day for this world to end, Allah will prolong that day to such an extent that He will send a man from my progeny, whose name will be my name. Salman (a.r.) stood up and asked, “O Messenger of Allah! He will be from the progeny of which of your sons?” The Holy Prophet (peace be upon him and his holy progeny) placed his hands on the shoulder of Imam Husain (peace be upon him) and said, ‘His progeny’”.
Every Mulsim in this world performs a good action in the hope of reaping rewards of his actions on the Day of Resurrection. But, from these two traditions, we realise that the reappearance of Imam Mahdi (a.t.f.s.) is such an enormous divine affair without which the Day of Resurrection cannot be established, even if there is just a solitary day left for the world to end. In other words, the Day of Resurrection is also awaiting the Reappearance of Imam Mahdi (a.t.f.s.).
O Allah, hasten the reappearance of the axis of the universe, the hope of humanity, heir of Imam Husain (a.s.), His Eminence the Master of time (a.t.f.s.) and help us unite upon the belief in his Imamate and Mastership.
Aameen, O Lord of the worlds!