Did the Qur'an mention when the Mahdi will emerge to save Muslims?

A Muslim must know that the Qur'an and the Sunnah (definition) are revelations from Allah, and that they are of equal standing in terms of their authoritativeness and the obligation to follow them. Allah has commanded obedience to the Messenger as an independent obedience. Neither the Qur'an nor the Sunnah explicitly state when the Mahdi will emerge, but his emergence is among the final minor signs of the Hour. Many have claimed that the Mahdi has emerged or will emerge for personal motives and misguided beliefs. Some have rejected the hadiths about the Mahdi or interpreted them to mean that the descent of 'Isa (Jesus), peace be upon him, is intended, citing the hadith (definition) "There is no Mahdi except 'Isa son of Maryam," which is a weak hadith. Many scholars have written extensively affirming his emergence and consider it part of a Muslim's creed. It is confirmed in the Sunnah that he will meet 'Isa ibn Maryam, and that 'Isa will pray behind him. A Muslim should not wait for the emergence of the Mahdi; rather, he should hasten and strive to work for the triumph of the religion and to reform himself and those around him.