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. 

We know leaders, kings, and queens by their power and might and sometimes feel terrified hearing their names. Those in power, usually, being occupied with many apparently vital matters, forget about those beneath them, the deprived ones. But, looking at the life of Imam Ali (AS), the commander of faithful and Prophet Muhammad's (PBUH&HP) rightful successor, we find a leader whose manner was incomparable to the ones we've seen or heard about so far. He was the father of orphans, a provider for the needy, and the defender of justice. 

In what follows, we will have a glance at the life of this exceptional Islamic figure of all time. 

1. His Birth and Lineage 

Imam Ali (AS) was born inside the Ka'ba in Mecca on September 28, 600 CE [1]. He was from Banu Hashim branch of Quraysh. His mother was Fatima bt. Asad and His father, Abu Talib, a respected man by various Arab tribes, was the uncle and guardian of the Prophet (PBUH&HP) and was of the most celebrated personalities of the Quraysh [2]. 

2. Imam Ali (AS)'s Relationship with Prophet Muhammad (PBUH&HP)

When he was six years old, a famine took place in Mecca. Since Imam Ali's (AS) father had a large family and providing for them in that situation was a difficult job, Prophet Muhammad (PBUH&HP) and his uncle, al-'Abbas, decided to help him. Therefore, they offered to take care of his children. So, Prophet Muhammad (PBUH&HP) took Imam Ali (AS) under his own guardianship [3]. Imam Ali (AS) recounted those days as such:

"When I was a young child, the Prophet (PBUH&HP) took care of me. He would bring me to his chest and I would sleep in his bed, so close to him that I could even smell his scent. He would chew food for me and then feed me with it. He found no lies in my speech, nor any shortcomings in my actions" [4].

When the prophethood assigned to Muhammad (PBUH&HP) in 610 A.D in Hira cave through Gabriel sent by Allah, Imam Ali (AS) was the first man, and Khadija (AS) was the first woman to acknowledge his call and believed in him. The ten-year-old Ali (AS) at the time would pray with the Prophet (PBUH&HP) on the mountains around Mecca [5]. He also supported Prophet Muhammad (PBUH&HP) when he was ordered to announce his mission publicly, starting with his close relatives. In return, Prophet Muhammad (PBUH&HP) declared him as his brother, executor of his will (Wasi), and successor [6]. 

In 615 A.D, Polytheists besieged Muslims in a valley called Abu Talib, where they were prohibited from trade and were under severe sanctions. During this challenging time, Imam Ali (AS) and his father Abu Talib, devotedly helped Prophet Muhammad (PBUH&HP). To save the Prophet's (PBUH&HP), which was under the threat of polytheists, Imam Ali (AS) risked his own life and even slept where Prophet Muhammad (PBUH&HP) used to sleep. The most well-known account of this sacrifice is when after Abu Talib's demise, Prophet Muhammad (PBUH&HP) decided to immigrate to Medina. He was informed of the secret plan of polytheists to murder him on the night when he was ready to start his journey to Medina. As a counteract, Imam Ali (AS) slept in Prophet Muhammad's (PBUH&HP) place, so that he could secretly leave his house to Medina [7]. A few days later, Imam Ali (AS), along with his mother and Prophet Muhammad's (PBUH&HP) daughter, lady Fatima (AS), joined the Prophet (PBUH&HP) in Medina. 

In 632 A.D, Imam Ali (AS) accompanied Prophet Muhammad (PBUH&HP) on his last pilgrimage to Mecca [8]. After the Hajj, on his way back to Medina in an area called Ghadir Khum, the Prophet (PBUH&HP) proclaimed Ali (AS) to be his successor and the executor of his will [9]. This event is known as the Event of Ghadir Khum and is celebrated by many Muslims around the world.

 3. His Marriage to Lady Fatima (AS) and Their Children

Imam Ali (AS) asked Prophet Muhammad's (PBUH&HP) daughter's hand in marriage. He consulted this request with his daughter, lady Fatima (AS), and after realizing her willingness to marry such an honored and pious man, Prophet Muhammad (PBUH&HP) consented to their marriage. 

There is a disagreement on the exact date of their marriage; however, the most accepted one is on May 25, 624 A.D [10]. Together, they had five children named Hasan, Hussain, Zaynab and Umm Kulthum [11] and also Muhsin, who was aborted before his birth.[12]

4. Imam Ali (AS)'s Government

After Prophet Muhammad's (PBUH&HP) demise and despite his speech in the incident of Ghadir, while Imam Ali (AS) and the Prophet's (PBUH&HP) family were busy with his burial, a group of the heads of Medina gathered in a place called Saqifa Bani Sa'ida to choose a successor for the Prophet (PBUH&HP) from themselves [13]. As a result, Abu Bakr was chosen as the caliph of Muslims, which was followed by Umar ibn Khattab's caliphate and then Uthman b.Affan. 

Finally, in June, 656 A.D and after the assassination of Uthman, Imam Ali (AS) became the caliph and the leader of the Muslims. Two days after the beginning of his caliphate, in his first sermon, Ali (AS) urged that all the wealth and properties that had been unjustly taken must be returned, and emphasized justice concerning the distribution of public properties and wealth [14]. 

As George Jordac, the Lebanese Christian writer puts: 

"In the eyes of Ali son of Abu Talib rulership and caliphate did not mean that the ruler should sit on the throne of dignity, strengthen his power and make his position the means of enslaving the people… Caliphate does not mean that people should be subjugated at the point of the sword, and by means of bloodshed and force, or that they should obey the caliph on account of fear or covetousness. Ali was a man who did not worship God because he desired forgiveness or because he feared punishment. On the contrary, he worshipped God because He deserved to be worshipped. He wished that the people should obey the caliph on account of his being worthy of obedience and not because of fear or greed of gain" [15]. 

During his four-year rule, he never did injustice to a soul, and he distributed wealth among people fairly, was observant of the poor, orphans, and the homeless. He was more like a compassionate father to people than a mighty unapproachable ruler. He lived a simple life, as he thought his life had to be like the poorest in society. He never favored any of his relatives over others in his government and refused to give them what they didn't deserve or had not any right to. In short, his government was the best instance of an ideal Islamic political and social system. 

5. His Eminent Characteristics 

As Prophet Muhammad (PBUH&HP) said in a narration Imam Ali's (AS) virtues and merits are impossible to number [16]. Nevertheless, we will try to mention some of his most significant characteristics. 

His Unbound Compassion and Generosity 

Kindness and compassion was an inherent characteristic of Imam Ali (AS). Poor or rich, young or old, Muslim or non-Muslim, man or woman, all would enjoy his regard and profound generosity. It is said that he used to water the date gardens of Jews in Medina with his own hands [17]. Jordac describes this characteristic of him as such:

"Ali was more kind to the people than anyone else and refrained from harming any person. He became oblivious of his own self in order to assist others and considered this self-abnegation to be part and parcel of his life. His entire life was dedicated to the support of the oppressed and the helpless so that he might realize their rights from the tyrants who considered themselves entitled to usurp the rights of others on account of noble descent and racial discrimination." [18]

This noble character was so kind that he refused to take revenge from the person who attacked him while praying in the mosque, which caused his martyrdom a few days later. He forbade his children to bring any harm to this person and commanded them to give him food and drink instead and treat him respectfully. 

His Wisdom and Sagacity 

Prophet Muhammad (PBUH&HP) said: "I am the city of knowledge, and Ali (AS) is its gate, whoever wants to enter this city, has to pass the gate first." [19]. Allah had endowed Prophet Muhammad (PBUH&HP) a breath of His divine wisdom, so when he calls Imam Ali (AS) as "the gate" to this divine wisdom through which people can enter, he is considering Imam Ali's (AS) wisdom as the prerequisite for reaching out to this vast knowledge.

As Jordac puts: "Ali was brought up by his cousin. He became his disciple and adopted his habits and conduct. The Prophet's heritage became implanted in his heart and brain. He reflected over the Qur'an with the intellect and eye of a sage and learned its latent realities" [20]. 

Imam Ali (AS) himself used to invite people to ask him their questions before they lost him since he was sure he would answer them in the wisest manner possible [21].

His Regard for the Needy

Imam Ali (AS) used to fast during the day and give away his food to the poor at night and slept hungrily. Based on an account, he and his family fasted for three days, and each night gave away their Iftar to one needy person who had come to their door. Some interpreters of the Quran believe that this act of Imam Ali (AS) and his family was followed by revealing this verse of the Quran [22]: 

"Those who give their wealth by night and day, secretly and openly, they shall have their reward near their Lord, and they will have no fear, nor will they grieve" (2:274)

He also gave away the money he earned through labor and tied a stone to his stomach to fight off his hunger. Whenever he gained a considerable amount of money, he informed the poor and the needy of it and divided it between them and then gave thanks to Allah through performing Salat [23]. 

According to some hadiths, one day a beggar entered the mosque and asked for help; but, no one gave him anything. He raised his hands toward the sky and said, "O God! Witness that I asked for help in the mosque of Your Prophet (PBUH&HP) and no one gave me anything." When he said this, Imam Ali (AS) was performing ruku' in prayer and pointed to the small finger of his right hand which had a ring on. The beggar went near and took the ring off from Imam's (AS) finger. Some exegetes believe [24] that this verse of the Quran referred to this incident: "Your guardian is only Allah, His Apostle, and the faithful who maintain the prayer and give the zakat while bowing down" (5:55). 

His Pure Faith and Piety 

He loved Allah, and his love was not tainted by fear or expecting a reward. His worships and prayers were purely for His sake and with the intention of His satisfaction; "The basis of this worship is reason, conscience, and spiritual perfection" [25]. This deep and pure faith that had penetrated his very bones turned him into a self-aware and pious man who aligned his every action with Allah's will and commands. As Jordac puts: 

"Ali's piety was not the outcome of circumstances like that of other pious persons, who engage themselves in worship on account of the weakness of their souls, or to escape the vicissitudes of life and to keep aloof from the people, or in imitation of their ancestors, and the effects of the events of life confirm it because as a rule, people accord respect to ancestral customs and traditions… His worship was, in fact, a continuous effort and a campaign against mischief for the sake of human life and prosperity… According to Ali, the essence of piety is to sacrifice one's life for the sake of truth and justice" [26]

He was born in the house of Allah, Ka'aba, and martyred in his dwelling, the mosque. As if Allah had destined him to always be in His arms.

His Courage and Bravery 

Imam Ali (AS) said: "Your faith should be at such a level that you should prefer truth to falsehood even though it may cause you loss and falsehood may bring you gain" [27]. And he did so in practice. He would choose truthfulness no matter what the result and never surrendered to injustice.

Another sign of his bravery was his disapproval of going into a war. Despite his strength and high physical power, he would rather peace and would not start a war unless it was inevitable. However, when he attended a battlefield, he fought courageously and never escaped from the enemy. Even on the battlefield, he was the forgiving man who pardoned his enemy when he found them defeated and defenseless. 

6. His Martyrdom 

On the morning of January 26, 661, Imam Ali (AS) was struck with a poisoned sword of Abd al-Rahman b. Muljam al-Muradi who was one of the renegades (Kharijites) [i] while performing Salat in the Grand Mosque of Kufa (today's Najaf in Iraq). He was martyred from this injury two days later and was buried secretly at his request [28]. 

Imam Ali, The Beacon of Justice and Humanity

Imam Ali's (AS) exemplary character and life can be a guiding light for all truth-seeking human beings. His deep affection for people, his care for justice and equality, his social and political insight, and his sincere devotion and faith in Allah made him a man whose fame reaches out to generations centuries later than his martyrdom. 

Notes:

[i] Khawārij or Kharijites were a group of Muslims who rioted against Imam Ali (AS) in the middle of, and after, the Battle of Siffin, as well as in the event of Arbitration. They then began the Battle of Nahrawan against the Imam (AS).

References:

 

1. Mufīd, al-Irshād, vol. 1, p. 5.
2. Ibn Athīr, Usd al-ghāba, vol. 1, p. 15.
3.  Ibn Hishām, al-Sīra al-nabawīyya, vol. 1, p. 162.
4. Nahj al-balagha, Sermon 192, p. 222. 
5. Muṣāḥib, Dāʾirat al-maʿārif-i Farsī, vol. 2, p. 1760.
6. Muhammad ibn Jarir al-Tabari, History of the Prophets and Kings, vol.2, p.331. 
7. http://en.wikishia.net/view/Laylat_al-Mabit
8. Ibn Saʿd, al-Ṭabaqāt al-kubrā, vol. 2, p. 131.
9. Ayyāshī, Tafsīr al-ʿAyyāshī, vol. 1, p. 4.
10.  Mufīd, Masār al-Shīʿa, p. 17.
11. Masʿūdī, Ithbāt al-waṣīyya, p. 153.
12. Ibn Shahrāshūb, Manāqib Alī b. Abī Ṭālib, vol. 3, p. 133.
13. http://en.wikishia.net/view/Incident_of_Saqifa
14. Nahj al-Balagha, Sermon 15. , p.39.
15. George Jordac, The Voice of Human Justice (Sautu'l ' Adalati'l Insaniyah), p.72. PDF.
16. Yusuf b. Qazawughli, Tadhkirat al-khawas, p. 13.
17. http://en.wikishia.net/view/Imam_%27Ali_b._Abi_Talib_(a)#Moral_Characteristics
18. George Jordac, The Voice of Human Justice (Sautu'l ' Adalati'l Insaniyah), p.33. PDF.
19.  Al-Hakim al-Nishapuri, Al-Mustadrak alaa al-Sahihain, vol.3, p. 126. 
20. George Jordac, The Voice of Human Justice (Sautu'l ' Adalati'l Insaniyah), p.40. PDF.
21. Ali ibn Abd-al-Malik al-Hindi, Kanz al-Ummal, vo.13, p.165. 
22. Abbas Qomi, Muntahi al-Amal, vol.1, p.284. 
23. al-Shaykh al-Saduq, Al-Amali, p.169. 
24. Ḥākim al-Ḥaskānī, Shawāhid al-tanzīl, vol. 1, p. 209-239.                                                                                         
25. George Jordac, The Voice of Human Justice (Sautu'l ' Adalati'l Insaniyah), p.29. PDF. 
26. ibid, p.28. 
27. Mohammad-Baqer Majlesi, Bihar al-Anwar, vol.70. p.106. 
28. Mufīd, al-Irshād, vol. 1, p. 27-28.