Irrespective of their sects, Muslims throughout the world believe that, "When Imam Mahdi (a.t.f.s.) will establish his government, peace, brotherhood, equality, justice and equity will spread to every nook and corner of the world. He will rescue the oppressed ones from the hands of the tyrants. And everybody will enjoy the bounties of the nature equally. He will establish such a government which will be free from all tyranny and evil. It will be free from war and bloodshed." For, the aim of rising of Imam Mahdi (a.s.) will be to establish peace and equity.
Holy Quran in different ways and at different places has prophesied that the pious and the weak will be the inheritors of this world. In other articles we have discussed the verses in detail.

Traditions about Justice
Holy Prophet (s.a.w.a.) in a very comprehensive and eloquent way has prophesied about the Justice of Imam-e-Zamana (a.t.f.s.). He says "Allah will raise a man from my progeny. He will fill the earth with justice and equity as it would be filled with tyranny and oppression."
In the initial part of this tradition he (s.a.w.a.) has assured us that before the world comes to end, it will be filled with equity and justice.

Cause of Expedience
A few questions may arise in our minds "Why is Allah delaying the establishment of a government of peace and justice? Why did He not set up a universal, just government right from day one? Why was the earth not filled with peace and justice in the times of the previous 13 infallibles? Why is this characteristic ascribed only to Imam Mahdi (a.t.f.s.)? Why did Holy Prophet (s.a.w.a.) have to prophesize this (just government) for the last period of the world?
Before answering the question, it is necessary to state that peace and justice is such a thing, that every human being loves it and strives to establish it. And the one who achieves peace and justice is the most liked person. If this characteristic is found in a governor or a leader or in his government, then such a person is considered as reliable and liked by all. This is because the love for peace and justice lies in the innate nature of man.
If we analyze human history, we will come to this conclusion, that despite liking peace and justice, till today, there is not a single instance of a leader, during whose rule this world was filled with peace and justice. Yes for a short span of time within some limits, Prophet Sulaiman (a.s.)'s kingdom was an example of peace and equality. It has been mentioned in the Holy Quran in Surah Saba, Surah Nisa, Surah Ambiya, Surah Naml, etc. that all the creatures including animals and birds, were submissive to him. Whatever he wished, like constructing a palace, masjid or cooking food, was done by the jinns before the batting of an eyelid. But even in his period, one cannot say that there was total justice and peace in the world.
Now let us try to understand why the Almighty has kept the just and equitable government for the last period of time. Imam Baqir (a.s.) remarked, "Our government is the final government. No family will remain who has not ruled the world. But their rule shall be prior to ours. This is because they should not have a chance to say after seeing our government and principles, that if we had the opportunity, we too would have ruled the world in the same way. And this is the meaning of Allah's words, 'The end is for those who fear (Allah)'."
(Behaarul Anwaar, vol. 52, pg. 332)

Justice for Name’s Sake
Our discussion revolves around the fact that justice is in the nature of man. Yet, we find that human beings are generally inclined towards injustice. In the present world, justice and equity is for name's sake. Very few people act with justice. Every group is busy in securing its own ends and even goes to the extent of trampling upon the rights of others. Even religious groups are not free from such defects. The unjust people propagate the name of justice and equity for their personal motives and the ordinary people are hoodwinked by their deceit.
We shall explain in brief the meaning of justice and then examine the Justice of Imam Mahdi (a.s.) in the light of the traditions.

The Meaning of Justice
The opposite of justice is oppression. Hence we can understand the complete justice of Imam Mahdi (a.s.) only when we have fully realized the extreme limits of oppression. The traditions quoted by us in the beginning also state that Imam Mahdi (a.s.) will fill the earth with justice and equity just like it would be overflowing with injustice and oppression (before him). Thus the vision of justice is based upon the eradication of oppression.

List of Oppressions
It is a very long list. It is not possible to mention each and every type of oppression in this article. However, we shall brief some of the types of injustices that will be eradicated after the reappearance of Imam-e-Zamana (a.t.f.s.). Polytheism - a great injustice "Certainly, polytheism is a great injustice."
(Surah Luqman, Verse 13)
It is said that injustice implies keeping a thing in the wrong place. To consider Allah in any position other than His actual position is injustice.
Imam-e-Zamana (a.t.f.s.) will destroy the foundations of polytheism and satan worship. The entire world will become a cradle of La Ilaha Illallah (There is no God except Allah). The Almighty Allah has thus stated, "All the creatures of the heavens and the earth obey Allah willingly or unwillingly and to Him they shall return." (Surah Ale Imran, Verse 83)
The actualization of this verse will be achieved during the time of Imam Mahdi (a.s.). He (a.s.) will destroy the greatest injustice i.e. polytheism and there will be no religion except the true religion of Allah. Allah will fulfill His promise through the reappearance of Imam Mahdi (a.s.).

What Is Justice?
Since the topic of discussion is the justice of Imam Mahdi (a.s.), we must comprehend the actual concept of 'justice' and its distinguishing features. Only then can we see if those characteristics are to be found in the government of Imam Mahdi (a.s.). The author of Misbahul Lughat (Arabic Urdu dictionary) has mentioned that the meaning of justice is "moderation in affairs", "equity", "to be straight".
Similarly the author of Al Munjid has defined justice to be the opposite of oppression. In the same way, the Arabic English Dictionary of J.M. Cowans mentions the equivalents of justice as straightness, straightforwardness, impartiality equitableness, fairness, honesty, uprightness, probity, etc.
Thus we can say that all the litterateurs have equated justice with the above qualities.
The traditions also compare the mission of Imam-e-Zamana (a.t.f.s.) to the perfect conditions of justice, equity and peace. Let us now examine some of the traditions:
Allamah Mohsin Amin (r.a.) has quoted from the Sahih of Muslim that the Holy Prophet (s.a.w.a.) said: "Listen to the good news of your Mahdi (a.s.) }’s advent... He will fill the earth with justice and equity like it would be full of injustice and oppression. The creatures of the earth and the sky will be pleased with him. He will distribute wealth equitably."
(Ayaanush Shiah)
A person inquired from the Prophet (saw) as to what is meant by equitable distribution of wealth. The Messenger of Allah (s.a.w.a.) replied, "To deal with the people justly."
Explanation: "The creatures of the earth and the sky will be pleased with him." Those people or that government which is impartial and absolutely just will deserve the love and admiration of all the creatures. On the other hand, people are dissatisfied even if there is little inequality and partiality. It is natural to oppose injustice. Since the government and its behavior is to be perfectly just, all the people will be pleased with him."
(Ibid., Part 4, p. 119)
In another tradition, Imam Jafar Sadiq (a.s.) says "When the Qaem rises, he will establish his government on the foundations of justice. Injustice and oppression will be eradicated during his tenure. The roads will be completely safe; the earth will throw out its bounties. The rights shall be restored to their owners. At this time, the earth will throw out its treasures and manifest its bounties. It will not be possible for you to find a needy person whom you can pay charity."
(Behaarul Anwaar, vol. 52, pg. 338; Aayanush Shia, Part 4, pg. 348; Kashful Ghumma, vol. 3, pg. 255)
(Note: Poverty, deprivation and lack of wealth are not due to any deficiency. They are due to the injustice and oppression, trampling of the rights and the destruction of wealth. Poverty results from the injustice of the oppressors when they subdue their weak fellowmen.)
Thus the tradition emphasizes that the earth will give out its underground treasures and bounties. It indicates that during the time of Imam-e-Zamana (a.s.) there will not be any shortages. Thus the question of theft and burglary does not arise. The unjust and the oppressive people will be eliminated by Imam (a.s.). And as we have seen in the previous tradition, "All the creatures of the earth and the sky will be pleased with Hazrat (a.s.)." This proves beyond doubt that the principles of justice will be in complete force. Otherwise it is not possible to please every creature at one and the same time.

A Glimpse Of Hazrat (a.s.)’s Time
Allamah Majlisi (r.a.) has quoted from "Khisaal" of Sheikh Saduq (r.a.) that Ameerul Momineen Ali (a.s.) said, "The Almighty Allah initiated, the religion through us and, He will conclude it through us. He will provide everything through us and give life to whomsoever he likes (through us). He will remove the difficulties of the times through us and cause rainfall. Then do not be arrogant and do not move away from Allah. Our Qaim will rise and the rains will descend from the sky. And the earth will throw out the minerals. How submissive they would be to the hearts of Allah's creatures. The wild animals will inhabit together without violence. Even if a woman travels alone from Iraq to Syria, she will be safe enough to halt at any place. She may carry her jewelry over her head but none will dare to loot her. (There will be no robberies). No wild animal will attack her. She will have no fear of them."
(Behaarul Anwaar, vol. 52, pg. 316)
Based on these principles of justice and equity the following developments shall take place:
• Complete eradication of difficulties
• Increase in bounties and general prosperity
• Hearts free from malice and enmity
• Women can travel alone in perfect safety. There will be no robberies and thefts.
The Holy Prophet (s.a.w.a.) has repeated this Divine Promise on numerous occasions. Consequently, most of the scholars have recorded the following tradition among the reports concerning the advent of Mahdi (a.s.).
"He will fill the earth with justice and equity like it would be replete with injustice and oppression." The majority of the scholars have narrated this tradition on Imam Mahdi (a.s.). Every Muslim visualizes him as a universal reformer who will bestow absolute peace to the world of turmoil.
The Holy Imams (a.s.) have stressed on more invocations for his reappearance and also mentioned the following characteristics in other supplications, O Allah! manifest Justice by him and assure a prolonged existence for the earth." "And manifest the justice through him and fill the earth with justice. O Allah! fill the earth with justice and equity like it is brimming with injustice and oppression."
(Majmua Adeeya wa Ziaraat, p. 126)
May Allah bestow on us the divine opportunity to pray for the reappearance of Imam-e-Zamana (a.t.f.s.).