The Arrival

The emergence of Imam Mahdi Mahdi is not because the will itself but because of God's destiny that certainly applies. Even Imam Mahdi himself did not realize that he is Imam Mahdi but after Allah told him in one night, as was said in a hadith the following:

"Al-Mahdi from my Ummah, who will be notified by God in one night. (Narrated by Ahmad and Ibn Majah) "

The emergence of Imam Mahdi will be preceded by some signs as mentioned in some of the following hadith:

Umm al-Mumineen Aisha RA to have said:

"One day the Prophet Muhammad's body vibrating in his sleep. Then we asked, 'Why are you doing something never done thee, O Messenger of Allah?'  the Prophet SAW said, 'There will be an oddity, namely that a group of people from my Ummah will go to the House (Ka'bah) to hunt down a man of Quraysh who fled went to the Kaaba. So if these people have come to the desert, then they were swallowed by the earth. ' Then we asked, 'Is not in the way of the desert there are all kinds of people?' He replied, 'Yes, among those who are swallowed by the earth is there that intentionally go to war, and some are forced to fight, and there are those who are in a journey, but they perish in one time and same place . While they come from the direction (intention) different. Then Allah will raise them on the Day of Resurrection, according to their intentions. (Narrated by Bukhary, Muslim) "

Prophet Muhammad has said:

"A man will come to the House (Kaaba), then send an envoy (by authorities) to catch up. And when they had arrived at a desert, then they are immersed swallowed by the earth. (Narrated by Muslim) "

Prophet Muhammad has said:

"A people who have the number and strength that does not mean going back to the House. Then sent (by authorities) a group of soldiers to pursue them, so if they had come to a desert, then they swallow the Earth. (Narrated by Muslim) "

The Prophet  SAW has said:

"Really, this House will be attacked by an army, so that when the troops had arrived at a desert, then the center of the troop was swallowed by the earth. Then yell troops to the front of the rear of the troops, where they were drowned and then all the earth and nothing remains, except a person who survived, who would preach about what happened to them. (Narrated by Muslim, Ahmad, Nasa'i, and Ibn Majah) "

Prophet Muhammad has said:

"It would be inducted into a male between the tomb of Abraham with the Kaaba angle. (Narrated by Ahmad, Abu Dawud) "

Prophet Muhammad has said:

"An army of my people will come from the direction of the country Sham to the House (Ka'bah) to pursue a man who would be kept from their God. (Narrated by Ahmad)