Mahdi (as) is a messianic figure in Islamic eschatology who is believed to appear at the end of times to rid the world of evil and injustice. He is said to be a descendant of Prophet Muhammad (PBUH& HP) who will appear while Jesus Christ (Prophet Isa-ibni Maryam) accompanying him and will lead the believers to rule the world and fill it with justice and peace. This is what the Quran says:

 And We wanted to confer favour upon those who were oppressed in the land and make them leaders and make them inheritors. (Al-Qasas 28:5)

Who is Mahdi (as)? 

The name Mahdi is derived from the Arabic root h-d-y, commonly used to mean "divine guidance". Though Imam Mahdi features in both Shia and Sunni understandings of Islam, they differ in his attributes and status. Among Twelver Shi’as, Mahdi is believed to be the son of the eleventh Imam, Imam Hasan al-Askari (d. 874), and is said to have been on divine occultation (ghaybat) by God’s will. However, the Sunnis assert that he (Imam Mahdi) is a descendant of Lady Fatimah (SA), the daughter of the Prophet Muhammad, and it is unknown whether he was born or not.

What is the View of Muslims About Mahdi (as)?

According to our belief, one of the most extraordinary acts of worship is to wait for the promised saviour, and this waiting means trying to provide the conditions for his reappearance.

In the Shi'a Islam, or the school of Ahlul-Bayt, the eschatological Mahdi was commonly given the epithet al-Qa'im, which can be translated as “he who will rise”, signifying his rise against tyranny in the end of all times. Distinctively Shi'a is the notion of the temporary occultation of Imam Mahdi, whose life has been prolonged by God’s will.

As in above mentioned, the Sunnis also believe in the promised Mahdi and many hadiths about him have been narrated in their books. Abu Dawood quotes Prophet Muhammad (PBUH & HP) as saying: " Mahdi will be from my household, from the descendants of Fatimah”. And another hadith states: “Even if only one day remains [until the doomsday], God will lengthen this day until He calls forth a man from me, or from the family of my house, his name matching mine and his father's name matching that of my father. He will fill the Earth with equity and justice just as it had previously been filled with injustice and oppression”. (Furnish, 2005, p. 14) According to narrations before the arrival of Imam Mahdi, the earth would be filled with chaos. While divisions and civil wars, moral degradation, and worldliness would be prevalent among people, injustice and oppression would be rampant throughout the world. The Dajjal (The Anti-Christ) would appear and will spread decadence and corruption in the world. With an army bearing black banners, which would come to his aid from the east, Imam Mahdi would confront the Dajjal. Jesus would pray behind Imam Mahdi and then will kill the Dajjal. The Sufyani, another representative of the forces of the dark, also features in the traditions. He will rise in Syria before the appearance of Imam Mahdi. When the latter appears, the Sufyani, along with his army, will either be swallowed up en-route to Mecca by the earth by God's command or defeated by Imam Mahdi.

What Role does he have in the Future of Humanity

In Imamiyyah (Twelver Shiism), the largest Shi’a branch, believing in the messianic imam is not merely a part of the creed, but is the pivot. For the Twelver Shi'a, Imam Mahdi was born but disappeared after a while, and he would remain hidden from humanity until he reappears to bring justice to the world at the end of time, a doctrine known as the Occultation. This Imam on occultation is the twelfth imam, named Muhammad, son of the eleventh Imam, Hasan al-Askari. According to the Twelvers, the Mahdi was born in Sammara around 868, though his birth was kept hidden from the public. He lived under his father's care until 874 when the latter was killed by the Abbasids. 

Shi'a scholars have argued that the prolonged lifespan of Imam Mahdi Mahdi is not at all unreasonable given the longevity of  the Prophet Noah, Khidr and Jesus, as well as secular reports about long-lived people. According to scholars Imam Mahdi is viewed as the restorer of true Islam, and the restorer of other monotheistic religions after their distortion and abandonment. He establishes the kingdom of God on earth and Islamizes the whole world. As a matter of fact, in their true form, it is believed, all monotheistic religions are essentially identical to Islam as "submission to God." It is in this sense, that one should understand the allegation that al-Mahdi will impose Islam on everyone. His rule will be paradise on earth, which will last for several years until his decease.[1]

References:

1. (Sachedina, 1981, p. 176-178)

The issue of art and drawings in Islam is among those topics that have not been directly mentioned and ruled on in the Quran. Therefore, one might wonder if drawings in Islam is allowed (Halal) or not and if yes, then are all types of drawings permitted (Halal)?

There are a few traditions narrated about drawings in Islam that are usually used to answer this question. However, since the answer can be derived from the Quran, this text tries to answer the question based on the Quranic verses. 
Now, you might be asking how it is possible to understand the ruling on drawing while there is no direct mention of it in the Quran. The answer is clear; the Quran provides us with a set of fixed frameworks that work as a criterion for us. And whenever we come to a question that we think was not an issue at the time of the Prophet (PBUH&HP), we can study it, based on the Islamic criteria and find the answer.

Does Allah Like Art?

Drawings in Islam and all other types of art are considered as tools to make things more beautiful and to create a feeling of admiration in their audience. Allah (SWT) has created this universe most superbly and has ordered all His creatures to admire and praise Him for this beautification. After creating the human, He looked at his creation and admired His own creation: “He formed you and perfected your forms, and provided you with all the good things. That is Allah, your Lord! Blessed is Allah, Lord of all the worlds!” (40:64)

Apart from the whole magnificent scenery of the universe, created by Allah (SWT), there are also some verses of the Quran that indicate the importance of beauty in the eyes of our Creator. And that is why the Prophet (PBUH&HP)’s saying, “Indeed Allah is beautiful and likes beauty” has become so famous [1]. The importance of beauty in the eyes of Allah is visible in different verses of the Quran: 

“O Children of Adam! Put on your adornment on every occasion of prayer … Say, ‘Who has forbidden the adornment of Allah which He has brought forth for His servants, and the good things of [His] provision?’” (7:31-32)

What Can We Find in the Quran about Art?

Creativity is a blessing with which Allah (SWT) has provided human beings (not to mention all the artistic creations of other creatures). And therefore, human beings have always created new things using their creativity, the effect of which is evident in the history and the Quran, e.g., in building houses, castles, making clothes, or designing jewelry, etc.

 However, the Quran does not admire all types of art. For example, making sculptures or figures to worship and as idols are considered to be negative. For instance, Prophet Abraham (PBUH), facing his people who were worshiping lifeless and dumb idols, addresses his father and says: “What are these images to which you keep on clinging?” (21: 52)

While in another Surah of the Quran, making statues and sculptures and other pieces of art so far as they are useful for human beings are referred to as positive and admirable. An example is when The Jinn built those pieces of art under the observation of Prophet Solomon (PBUH): “They built for him as many temples as he wished, and figures, basins like cisterns, and caldrons fixed [in the ground] …” (34:13).

Besides, the main ruling on doing artworks can be derived from a Surah in the Quran called Surah Al-Shu’araa’ which means Poets. 

In this Surah Allah (SWT) clearly describes the essence of forbidden (Haram) and allowed (Halal) art with a direct mention of poetry which was popular in Prophet (PBUH&HP)’s time:

 “As for the poets, [only] the perverse follow them. Have you not regarded that they rove in every valley and that they say what they do not do? Barring those who have faith, do righteous deeds, and remember Allah much often, and vindicate themselves after they have been wronged. And the wrongdoers will soon know at what goal they will end up.” (26: 224-7)

In these verses, Allah (SWT) states that only perverse people would follow and admire the poets. And in describing the poets, it is mentioned that “they rove in every valley,” meaning that they make up things from their imagination. At the time of the Prophet (PBUH&HP), ‘most poetries were about the beauty of women, adultery, and pervert behaviors.’ However, Allah (SWT) does not forbid poetry completely; rather, He ‘makes the exception of faithful poets’ in the next verse. ‘Those who use their art as a tool to defend justice and to reveal oppression and injustice.’ [2]

How Do I Know My Drawings in Islam Are Forbidden (Haram) or Allowed (Halal)?

From the above verses of the Quran, we can conclude that any form of art or any other tool is allowed (Halal) provided that they are used in the way of Allah, and if used in the way of Satan, they are considered to be forbidden (Haram). Therefore, it is of utmost importance to be familiar with the Islamic jurisprudence to distinguish the right from wrong from an Islamic viewpoint.

Another point that needs to be considered about different forms of art and drawing is that they should not go against the Islamic jurisprudence. Including erotic pictures or scenes in drawings or illustrations is one example of what makes this form of art forbidden. Therefore, as long as the drawing or making sculptures do not have any adverse harm for human soul and improvement, the ruling is as follows: “There is no harm at all in the sculpture, photography, and drawings of living beings whether or not they have a soul. Also, it is permissible to sell, buy, or keep pictures and statues. There is no objection to showing them in an exhibition as well” [3].

References: 

1. Al-Kafi. Vol. 6, p. 438
2. Tafseer-e Noor, Qara’ati, M. Vol. 6, p. 381
3. Painting and sculpture