Abd al-Aziz ibn Muslim narrated:
"Imam [Mahdi (pbuh)] is the order of the religion and the honor of Muslims. He is the target of the hatred of hypocrites, and is the means for the perishing of unbelievers. The Imam Mahdi (pbuh) is a unique personality in his own age; no one can reach his rank and no scholar could approach his knowledge. No one can be like him, nor can anyone be equal to him. He stands out with his virtues and possesses all the virtues. However, he [Mahdi (pbuh)] has not obtained these willingly or working hard. On the contrary, God grants all the virtues and goodness to him [Mahdi (pbuh)] as only unique to him."
(Book of Belief and Blasphemy, Usul al-Kafi (Al-Usul min Al-Kafi), Al-Kulayni, Volume 1, page 281)