According to the hadith, the Mahdi (pbuh) is the sum of all the prophets. He is the last guardian, the greatest saint of all-time and pure in judgment. Almighty God appoints an Ulu'l Azm [The Resolute Prophets] prophet like Jesus Messiah (pbuh) as a vizier of the Mahdi. This shows how esteemed the Mahdi is. - Harun Yahya