All Abrahamic religions believe in the return of the savior, the liberator of the human beings and redeemer, in the End-Time. Prophets and divine messengers have promised the day that the whole universe will be full of justice and tenderness. Other religions also have similar beliefs, although they differ in some minor aspects, which will be discussed below. We go through references from different religions and faiths to examine their views about the last savior. 

Kalki: The Last Savior in Hinduism

In Upanishads, which is a collection of ancient Sanskrit texts that contain some of the central philosophical concepts and ideas of Hinduism, the last savior is called Kalki. He is believed to be the tenth avatar of Hindu god Vishnu in the last of the four stages in the endless cycle of existence known as "Samsara," which is defined "as the endless cycle of birth, death, and rebirth. Or as the world of suffering and dissatisfaction (dukkha)" [1].  He rides a white horse with a fiery sword. He will end the darkest and destructive period to remove adharma [i] and will usher in the Satya Yuga [ii][2]. 

Another reference talks about a just commander at the end-time who is the leader of angels and humans, who knows the truth and gets hold of everything from deep in the seas too high in the mountains, and no one greater than him will come to earth [3].

Saoshyant: The Eschatological Savior in Zoroastrianism

In Zoroastrianism, there are three saviors who each will rise in a thousand years. The last one is an eschatological savior figure who will destroy evil and will bring about the renovation of the world. He is called Saoshyant, which means the beneficent in its single form. Yet, in its plural form, it is considered to mean the redeemer. The Khorda Avesta describes this savior as such:

Whose name will be the victorious SAOSHYANT and whose name will be Astvat-ereta. He will be SAOSHYANT (the Beneficent One) because he will benefit the whole bodily world; he will be ASTVAT-ERETA (he who makes the bodily creatures rise up), because as a bodily creature and as a living creature he will stand against the destruction of the bodily creatures, to withstand the Druj of the two-footed brood, to withstand the evil done by the faithful. [4]
Accordingly, the Soashyant will rise at the end-time and fight against the vices in the world and spread justice and goodness far and wide. 

Maitreya: The Future Buddha

In some of the Buddhist references, such as the Amitabha Sutra and the Lotus Sutra, we read about the future Buddha of this world, called Maitreya, who will be a successor to the present Buddha. In Sanskrit, Maitreya means kindness and love. According to Buddhist religious texts, Maitreya will be the fifth and last Buddha who will appear on the earth. The arrival of Maitreya is expected at a time in the future when the dharma will have been forgotten by most on the earth. That is when Maitreya will appear on the earth to achieve complete enlightenment and to teach the pure dharma [5].

Li Hong: The Last Savior in Taoism

The Taoist last savior, called Li Hong, is depicted as an ideal leader who would reappear to set right heaven (tian) and earth (dì) at a time of upheaval and chaos. Li Hong will appear at the end of the world cycle to rescue the chosen people, who would be distinguished by certain talismans, practices, and virtues [6].

Savior in Abrahamic Religions

Moshiach: The Last Savior in Judaism

The Jews belief in the savior is manifested in the idea of the coming of Moshiach (i.e., Messiah). This person is believed to be a descendant of King David, who will "gather the Jews from all over the world and bring them back to the land of Israel" [7]. There are many verses in different scriptures and Talmudic [iii] literature which refer to this figure and enumerate his characteristics and manners [iv]. For instance, Isaiah says:

And there shall come forth a rod from the stock of Jesse [King David's father], and a branch shall grow from his roots; and the spirit of the Lord shall rest upon him, the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and of the fear of the Lord. And his delight shall be in fear of the Lord; and he shall not judge by what his eyes see, nor decide by what his ears hear. But with righteousness shall he judge the poor, and decide with equity for the humble of the earth; and he shall strike the earth with the rod of his mouth, and with the breath of his lips shall he slay the wicked.
–Isaiah 11:1-4

Those who follow Judaism believe that their savior has not been born yet. Therefore, they are eagerly awaiting the coming of the one who will save them and establish a just dominion in which "there will be world peace, no more wars nor famine, and, in general, a high standard of living" [7]. 

The Messiah: Jesus Christ (PBUH) the Savior of Mankind 

Christians believe that Jesus Christ (PBUH) is himself the savior of humankind, and he was born for this purpose. The name Christ literally means "the anointed one" or the Messiah [8]. As the Gospel of Matthew says, Jesus Christ (PBUH) has been sent to "Save his people from their sins" (1:20-21). It is also believed that Jesus Christ (PBUH) had been crucified to atone the sins of humanity and lead them toward salvation. According to Christian sources, Jesus Christ (PBUH) was the savior who was awaited by the Jews as whose coming was predicted in the Torah as the Moshiach. 

Another point which makes Jesus Christ (PBUH) the awaited savior in Christianity is the idea of his second coming or the Second Advent in the end-time to whose "day or hour no one knows, not even the angels in heaven, nor the Son, but only the Father" (Mark 13:32). This is the belief in "the future return of Christ in glory when it is understood that he will set up his kingdom, judge his enemies, and reward the faithful, living and dead" [9]. Different gospels, including Matthew chapters 24–25; Mark, chapter 13; Luke, chapter 21:5–26, and John, chapter 14:25–29, are mentioned as the evidence for this belief. Moreover, according to biblical verses, there will be many signs indicating the end-time among which the second coming of Jesus Christ (PBUH) and the last judgment. 

Therefore, like many other religions, Christians also believe in a savior or as they call it the Messiah, who will make this world a better place and free it from oppression and injustice. 

Imam Mahdi (AS): The Awaited Savior in Islam

In Islam, the belief in the savior is rooted in the fact that Allah never leaves His creatures, especially human beings, on their own and support them through sending His apostles to guide them toward the right path: "and there is a guide for every people" Quran (13:7). He had sent 124000 prophets (PBUT) first, followed by righteous leaders who continued the path of previously chosen messengers of Allah. As the Quran says, "Certainly We wrote in the Psalms, after the Torah: 'Indeed My righteous servants shall inherit the earth.'" (21:105).

 Therefore, the earth will never become empty of Allah's guide, and people will benefit from these guiding lights either directly or indirectly. Imam Mahdi (AS), the twelfth leader of Muslims and a descendant of Prophet Muhammad (PBUH&HP), who is leading a secret life at the time, will ultimately rise and spread peace and humanity throughout the earth. "The Holy Prophet (PBUH&HP) informed Muslims about his reappearance, telling his names, attributes, appellations, and peculiarities" [10]. The time of his coming is unknown, and it is followed by the preparation of particular circumstances. 

The signs that indicate his coming include "Widespread injustice and oppression, the advent of Dajjal (Anti-Christ) who would misguide the thinking of the people, the advent of Sufyani who is one of the pillars of mischief and corruption on the earth, the formation of the Islamic army, which would raise up black standards, the voice of the angel of the sky giving glad-tidings of his reappearance, the coming down on earth of Jesus Christ (PBUH) and his paying allegiance to and praying behind in congregation Prayers led by Imam Mahdi (AS)" [11]

This belief in the last savior, who would stand against tyranny and injustice and remind human beings of their real value, also, highlights Islam's optimism toward the future of the world.

Finally, we have reviewed the belief in the last savior or the person who will save humankind from the evilness and destruction in this world in different faiths and religions. On a more in-depth look, we can find many similarities between these beliefs. However, the Abrahamic religions had a more precise and more tangible attitude toward the idea of the last savior and the time of his coming. Therefore, the concept of the savior is one of the most essential and significant matters regarding the future of human destiny. 

Notes:
[i] Opposite to dharma, which includes unnaturalness, wrongness, evil, immorality, wickedness, and vice. 
[ii] The period when humanity will be governed by gods and every manifestation or work is close to the purest ideal, and humanity will allow intrinsic goodness to rule supreme.
[iii] The central text of Judaism and the primary source of the Jewish religion. 
[iv] Isaiah 2, 11, 42; 59:20, Jeremiah 23, 30, 33; 48:47; 49:39, Ezekiel 38:16, Hosea 3:4-3:5, Micah 4, Zephaniah 3:9, Zechariah 14:9, Daniel 10:14. 

References:

1. Samsara
2. the man on the white horse
3. The Vishnu Purana, trans. Horace Hayman Wilson, London: Trübner & co., Book IV, Chapter 24.
4. Khorda Avesta, Translated by James Darmesteter (From Sacred Books of the East, American Edition, 1898.), Part five
5. Buddhism
6. Anna K. Seidel. "Perfect Ruler in Early Taoist Messianism: Lao-tzu and Li Hung." History of Religions, Vol. 9, No. 2/3
7. The end of days
8. what does christ mean
9. second coming
10. Sayyid Ali al-Husayni al-Milani, The Promised Savior: An inquiry into the imamate of Imam Mahdi (as) from the viewpoint of Muslim thinkers, part 1, p.8. 
11. Baqir Shareef al-Qurashi, The Life of Imam al-Mahdi, Trans. Sayyid Athar Husayn S.H. Rizvi, p.259-283. Pdf. 

Imam Rida (AS) is the eighth infallible Shiite Imam and successor of the final holy Prophet (PBUH&HP). His name is Ali, and among all his other names and titles the most famous honorary one is “Rida,” which means ‘satisfaction’. But why was he called this name?

According to his son, Imam Jawad (AS), “The Almighty Allah named him Rida because He was pleased with him in the heavens and the Prophet of Allah (PBUH&HP) and the Imams of guidance (AS) were pleased with him on earth” [1]. In fact, Imam Rida (AS)’s moral qualities and virtues were so high that even his enemies were attracted to and admired him. You might wonder what these traits are!

1. Imam Rida's (AS) Forbearance

Imam Rida (AS) was the exemplar of a patient man. There were times when he was treated disrespectfully, but he would not react and preferred to remain silent. It has been narrated that when Caliph Mamun[i] tried to degrade Imam Rida’s (AS) position through scientific and theological debates with the contemporary scholars of other religions and opponents, Imam would patiently make the best use of those meetings and introduced the true religion of Islam to the world.

2. Imam Rida's (AS) Modesty

While having a meal alone, Imam Rida (AS) would invite all his slaves, servants, including the Blacks, to have the meal with him at the same place. And when he was told to make separate eating arrangements for the servants, he would refuse and say: “We are all created by God, our parents (Adam and Eve) are the same, everyone will be dealt with by God according to their deeds” [2].

Once a man said to Imam Rida (AS): “By God, you are the best in the world,” but Imam replied: “Do not swear by the name of Allah. Anyone who is more pious than me can be better than me.” Then he recited the following verse of the Quran:

“O, humankind! Verily, We created you all From a male and female [Adam and Eve] and appointed for your tribes and Nations to be known to each other [by Specified characteristics] Verily, in Allah's Sight the most honorable of you Is the most pious of you; and Allah is The Informed Owner of Knowledge” (49:13) [3].

3. Imam Rida's (AS) Courtesy

Imam Rida (AS) would never hurt anybody with his words; He treated people as respectfully and kindly as possible; he would never talk badly to anyone or interrupt someone when speaking; he never stretched his legs or lean upon something in front of people. He always smiled instead of laughing loudly [4].

One night while Imam Rida (AS) was talking to his guest, there was a problem with the light. The guest wanted to fix it, but Imam did not let him do so. He started fixing it himself and said: “We are the ones who do not put our guests to work.”

Also, it frequently happened that Imam called a servant for some work, and he was told that the servant was busy having a meal; then Imam would say: “Let him finish his food” [5].

4. Imam Rida's (AS) Generosity

One day a foreign traveler came to visit Imam Rida (AS). After saying hello and expressing his love and affection towards Imam Rida (AS), his fathers and ancestors, he said he had come back from Hajj and had run out of money. He asked Imam to give him some money to go back home and promised to spend the same amount there on charity and giving alms (Sadaqah).

Imam stood up and went to another room. Then he came, stretched his hand from behind the door, and said: “Get this 200 Dinar and spend it for your journey, there is no need to pay the same back as alms.” The man got the Dinars and left. Imam later was asked for the reason for his secret help, and he answered: “Because I did not want the man to feel ashamed” [6].

Also, whenever Imam Rida (AS) wanted to have his meal, he would bring a large plate and put the best of the food on it to be given away to the poor. If he afforded to help, he would always give alms to the destitute at nights.

5. Imam Rida's (AS) Insight

In another account, One of Imam’s companions narrated that One day after he arrived home, he saw his servants busy repairing the house. Imam noticed a stranger among them and asked about him. They answered he was there to help them and they would pay him. Imam asked if they had defined the amount of payment.

The answer was no. Imam became disturbed and said: “when one works without any contraction, he thinks that you have paid him little, even if you give him three times more. But if you contract and pay him according to the contraction, he will be pleased with receiving his right. Now if you pay more even just a little, he will understand you have paid more and will be thankful” [7].

6. Imam Rida's (AS) Divine knowledge

Imam Rida (AS) had inherited the divine knowledge from his ancestor, our Holy Prophet, Muhammad (PBUH&HP).

He was the wisest man of his time and all his contemporaries. His knowledge was so rich in all religious matters and other realms of knowledge that the people of various tribes in their language would turn to him when they had questions, and he provided them with the best answers. Ma'mun, the ruling caliph, summoned the knowledgeable scholars in an attempt to defeat Imam Rida (AS) in several scientific debates and to discredit him in public. Nonetheless, Imam succeeded in all of them, and no one was capable of overcoming his power of knowledge.

Whoever dared to challenge Imam Rida (AS) ended up yielding to his unique power of reasoning. It has been confirmed by historians that Ma'mun, who was himself a celebrated erudite, pointed out the following statement, in his official charter for the appointment of Imam Rida (AS) as his immediate successor:

"I do not know any person superior to this man [Imam Rida (AS)] in the whole world" [8].

The life of Imam Rida (AS) and our other infallible Imams (AS) contains countless anecdotes of this sort, which reveals how they teach us the correct way of life both by their sayings and behaviors.

In a famous tradition or saying (Hadith) called the Golden Chain (Selselah al-Zahab), Imam Rida (AS) said that he had heard from dignified ancestors quoting from Gabriel and Almighty Allah that: “The word of La Ilaha Illallah -there is no god but Allah- is My stronghold (then whoever acknowledges this has entered My stronghold) and will be saved from My punishment”. After reciting this saying for his companions, Imam paused for a while and then continued, “Few conditions are entitling this entrance, and I am one of its conditions.”

Through this account, Imam Rida (AS) confirms that the belief in monotheism (Tawhid) will be counted as perfect when it is based on the obedience of the infallible Holy Imams (AS). In fact, Imams’ lifestyle and traditions were so good that if we idolize them and follow in their footsteps, we will certainly be able to move through the stages of spiritual perfection and win Allah’s satisfaction. Insha’Allah! 

Notes:
[i] The Abbasid caliph in power at Imam Reza’s (AS) time.

References:

1. Bihar al-Anwar, V.49, P.4.
2. Osool al-Kafi vol.8 p.230.
3. Oyoun Akhbar al-Reza, v.2, p.236.
4. Al-Fadl ibn al-Hasan Tabarsi, Aa’lam al-Vara p.314.
5. Osool al-Kafi vol.6 p.383 & 298.
6. Managhib vol.4 p.360.
7. Osool al-Kafi vol.5 p.288.
8. Al-Irshad, v.2, p. 261.