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. 

The Holy Quran is replete with examples of men who stood for the truth and those who opposed it. The former sacrificed everything they had to defend the truth and the latter was ready to destroy everything around them to satiate their greed and selfishness.

The Book of Allah invites us to reflect upon personalities, nations, and events of the past. Whether it is pure men like Prophet Ibrahim (AS), Prophet Musa (AS) and Prophet Isa (AS) or evil men who opposed them and their mission like Nimrood, Firon (Pharoah), or Bani Israil, all of them have a lesson for us. These are not just stories to read and move on, they contain messages for our lives. And rightly so, we read in the Holy Quran:
"There is certainly a moral in their accounts for those who possess intellect. This [Quran] is not a fabricated discourse; rather, it is a confirmation of what was [revealed] before it, and an elaboration of all things, and a guidance and mercy for a people who have faith. (12:111)

Similarly, Imam Ali (AS) says: Learn lessons from past events for future events, because they are similar to one another. (Nahjul Balagha Letter 69)
One such incident of the past that changed the history of Islam forever, is the event of Karbala. No mention of Karbala is complete without Hurr ibn Yazid Ar-Riyahi. He is an example for those who reflect upon his journey, his actions and his martyrdom. He encourages, inspires and motivates the believers through his actions in Karbala. 

Background

Hurr literally means a freeman in Arabic, and truly so he lived up to his name. 
Hurr Ibn Yazid Ar-Riyahi was the general of the Ummayad army dispatched from Kufa, (Iraq) to intercept Imam Al-Hussain (AS), the third infallible Imam. Ubaydullah ibn Ziyad, the newly appointed governor of Kufa issued the command to guard all entrances and exits to Kufa in order to intercept al-Hussain for an oath of allegiance to Yazid. Hurr was ordered along with his 1,000 soldiers to intercept Imam Hussain(AS) and his followers before they reached Kufa.

When he intercepted Imam Hussain (AS) at Dhu Hussam, Hurr and his men had ran out of water. The Imam(AS) ordered his companions to satiate Hurr and his army, including the cavalry. Hurr and his men offered their prayers with the Imam and listened to his sermons. However, on subsequent orders from the tyrant governor of Kufa, Ubaidullah Ibn Ziyad, Imam Hussain and his family were forced to encamp in Karbala. Hurr was of the notion that the Imam (AS) will not be killed in Karbala, he would somehow persuade him to go elsewhere. But he was perturbed when he realized that Umar Ibn Sa'ad who was sent by Ubaidullah had come with orders to kill Imam Hussain. On one hand was his position, family and wealth and on the other hand was the grandson of the Holy Prophet(PBUH&HP) and the son of Imam Ali (AS) and Lady Fatima (SA), supporting whom meant a certain death. These were the two options left for Hurr, just as the Holy Quran says:
 "Indeed We have guided him to the way, be he grateful or ungrateful." (76:3). 

What do we learn from Hurr?

Despite all odds, Hurr left the Army of Yazid, joined Imam Hussain (AS) and won the honor of being the first martyr of Karbala. All the glitter of the world, his power, rank, wealth and children did not stop him from joining his master Hussain(AS). 
Ashura and Karbala were not be bound by time or geographical location. Almost 14 centuries have passes by but human beings from different parts of the world, belonging to different races and religions continue to mourn for Imam Hussain(AS) and take inspiration from him and his mission.
Just as Karbala continues to inspire us, the magnanimous personality of Hurr continues to inspire and guide us. Hurr chose good over bad, truth over falsehood, hereafter over the transient world. If we claim to be followers and lovers of Imam Hussain(AS) we need to turn towards the Hussain of our time and follow the teachings of Imam Hussain(AS). Imam Hussain(AS) gave everything he had to protect and preserve the teachings of Islam and by helping Hussain(AS) in his cause, Hurr achieved this lofty position of being Imam Hussain's(AS) helper. Thus, if Hurr truly motivates us, we need to mend our ways and make ourselves capable of helping Imam Mahdi (AJ) the true inheritor of Imam Hussain's (AS) legacy.

The Hurr of Karbala teaches us that true love is incomplete without sacrifice. 

But, is the Hurr inside us ready to listen?

References

1. A Probe into the History of Ashura, Ibrahim Ayati