The evidence to prove his existence is from undoubted authentic narrations from the Prophet and the Imams (peace be upon them).

It is not correct to expect to have evidences of beliefs from the Holy Quran explicitly and in clear text form. It is clear that the Prophet (peace be upon him and his holy progeny) is perfect and infallible. In addition to that, Allah explicitly declared that he “he does not speak of (his own) desire” (53:3). Because of this, the Muslims believe in all that is established to be the Prophet’s words. And we find traditions of the Prophet (peace be upon him and his progeny) in the Muslims’ books about Imam Mahdi (peace be upon him) and that he is from the offspring of Imam Husain (peace be upon him).

The narrations of the Ahlulbait (peace be upon them) exhort the believers to pray for the hastening of the relief (faraj) of the Imam (peace be upon him). Aside from this, every devotee is expected to be a good example for others in his actions and behaviors to give a good impression about Islam and Shiaism. It was reported that the Imams said: “Call to us (our path) by your (good) deeds”.

There are many narrations from the Prophet and the Imams (peace be upon them) that whoever dies while he was waiting for our matter (i.e. for the government of the Imam) then he shall be considered like whoever died in battle for the Last Imam (may Allah hasten his reappearance), and the said is the best way of ending this life.

It is permissible, as it is a form of seeking his intercession to fulfill one’s needs.

There is no doubt that this claim is false. This person should be ignored regardless of his position in the society.

We advise you to stay away from this kind of thoughts and focus on performing what is obligated and recommended in the Sharia. Once you do that, you will be under the care of the Twelfth Imam (peace be upon him), even if you don’t directly feel his blessings.

It is reported in one of the letters of Imam Mahdi (may Almighty Allah hasten his reappearance) that was released by the last Safeer, that whoever claims that he sees him – the Imam – then consider the claimant as a liar. The righteous sect of Shiaism has been observing this since the first days of the major occultation.

It is permissible.

It has been reported in many narrations that the actions of believers are presented to the Imam of the time (may Allah hasten his reappearance) once a week.

One will please the Imam (peace be upon him) by acting upon the orders of Almighty Allah.
With respect to seeing him (peace be upon him), we are not aware of any deed that will lead to it.

It has been reported in a narration that Imam Mahdi (peace be upon him) said: "Benefitting from me in my absence is as benefitting from the Sun when its disappears behind the clouds.”

It is mentioned in some books. Allah know best.

Some books mentioned that the Imam (peace be upon him) lives in an island by the name of the Green Island, but we cannot confirm the truthfulness of this issue. Almighty Allah knows best.

It was narrated from the Imams (peace be upon them) that when he reappears again he would look like forty years old. Nobody knows saves Almighty Allah his original age after the reappearance.

Nobody knows the precise time except Almighty Allah and there is no need to search that as long as we cannot find out.

It appears from some of the narrations that there are three inevitable signs. They are: the rising of the sun from the west, and the cry from the sky that will declare the reappearance of the Imam, and the swallowing of the earth in the desert. Other signs are possible.
There is no doubt that Almighty Allah will establish undoubted clear evidence when he reappears, so it is better to delay paying attention to these issues to their designated times and not rushing to conclusions in this Godly matter, since He will clarify it at its appropriate time.

It is prohibited to falsely claim to be appointed directly by the Imam (peace be upon him) as his deputy.

There is no doubt that it is recommended to pray for the emergence of the Twelfth Imam (peace be upon him), for his health and the like.

Imam Mahdi (peace be upon him) does not have an eternal life; rather, he is promised to live a long life. He will appear to people when the circumstances are right to establish justice on Earth. After that, the divine law of death will include him. Almighty Allah said:” Lo! You will die, and lo! They will die;”
This long life is not common amongst most people, although it is proven to be for some, like prophet Noah (peace be upon him), who lived as a prophet before the flood for 950 years. In some narrations, Khidhr is also alive and he is older than Imam Mahdi (peace be upon him).
There is no cause for doubt about the Imam’s existence because of his long life, since the authenticated texts prove his presence and his Imamate.