Life is a journey full of twists and turns. Without a guide in this deceptive path, one can become lost, forfeiting something that cannot be regained - the precious gift of redemption. That is why Islam emphasizes the need for Muslims to never be without a leader. Prophet Mohammad (PBUH&HP) is the best example of a Muslim within Islam.

There has certainly been for you in the Messenger of Allah an excellent pattern for anyone whose hope is in Allah and the Last Day and [who] remembers Allah often. (The Holy Quran 33:21)

O you who have faith! Obey Allah and His Apostle, and do not turn away from him while you hear [him]. (The Holy Quran 8:20)

These Quranic verses firmly establish that no one surpasses Prophet (PBUH&HP) as the ideal role model, guiding us to emulate his actions and lifestyle for our salvation. When we follow someone as a model in our life, we inherently respect his beliefs and ideas. 

From this, we deduce that if our model is devoted to Islam, religion, and the path of Allah's pleasure, we will also try to align ourselves with that path and potentially attain spiritual ascension. Our model here is not an ordinary person but our dear Prophet. Therefore, there is no disputing the goodwill of this revered figure. An important thing that we must learn from the Prophet (PBUH&HP) as the supreme model for Muslims is to know whom to love and whom to dislike.

The question is: how does understanding Prophet’s feelings towards individuals would help us? 
The answer lies in this: “By following the Prophet as an example, we can accurately discern these people, subsequently progressing toward Allah’s satisfaction and eternal happiness.” 

Two figures whom the Prophet constantly favored were Imam Hassan and Imam Hussein (as). Imam Hussein (AS) was born on the third of Sha'ban in the fourth year of AH.

Since the great Prophet passing in the tenth year of AH, Imam Hassan and Imam Hussein (AS) spent their childhood with their dear grandfather.

Before delving further, let us know more about our third Imam. Imam Hussein (as) is also called Aba-Abdillah and Sayyid al-Shuhada among the Shias. He is the third Imam for the Shias, martyred in the course of Ashura. He is the second child of Imam Ali (AS) and Fatemeh Zahra (AS), and the grandson of Prophet Mohammad (PBUH&HP). Following his brother Imam Hassan’s (AS) leadership, he took charge of leading the Shias for ten years. Both Shia and Sunni historical records confirm that the Prophet of Islam (PBUH&HP) announced his martyrdom at his birth and chose the name "Hussein" for him. (1)

The Prophet held deep affection for Imam Hassan and Imam Hussein and recommended everyone to love them. Imam Hussein (AS) is one of the of Prophet’s Ahl al-Bayt and also one of the recipients of the verse of purification*.

Numerous narrations from Prophet Mohammad (PBUH&HP) extol Imam Hussain’s virtue. A famous narration quotes the Prophet (PBUH&HP) on Imam Hussain (AS): “Hussain is from me and I am from Hussain. Allah loves who loves Hussain.” (2)

Through this narration, the Holy Prophet (PBUH&HP) show other Muslims the sacred position of Imam Hussein (PBUH) and imparts the exceptional stature of this lineage. In an era where falsehood and hypocrisy infiltrate the Muslim community, this saying compels believers to rid themselves of hypocrisy and misguidance. 

Regrettably, despite its resonance, this profound message did not deter the brutal martyrdom of Sayyid al-Shuhada (PBUH), which transpired in the Karbala before thousands of seemingly Muslim individuals.

The Prophet’s (PBUH&HP) adoration for Imam Hussein (AS) served a dual purpose: it conveyed not only his love for his grandson, but also aimed to engender affection towards Imam Hussein as the Imam of the Ummah, rallying people to follow him. Therefore, the Holy Prophet of Islam consistently introduced the Imam Ali, Fatima Zahra, Imam Hassan and Imam Hussein (AS) as his family and Ahl al-Bayt. He equated them with the Quran on numerous occasions,  underscoring the necessity for Muslims to accept their leadership and guidance for spiritual elevation. The Prophet also said this in the hadith of the thaqalayn: 

"Indeed, I am leaving two things among you, to which if you hold yourself, you will never astray: the book of Allah –who is almighty and great- and my Ahl al-Bayt (household), my 'itra (family). O people hear! And I have announced to you that indeed you will enter my presence and I will ask you about what you did to the thaqalayn (two weighty things) and the thaqalayn are the book of Allah and my Ahl al-Bayt."(3)

Conclusion: 

These narrations illuminate Imam Hussein’s (AS) lofty status in the the Prophet’s (PBUH&HP)eyes and the Prophet’s responses to him serves as a guide. Not only are Muslims, as followers of the Holy Prophet, must praise and love Imam Hussein, but we must also adopt his behavior, thoughts, and ethics, and follow his path in our lives. Furthermore, the Prophet's interactions with Imam Hussein underscore that those who harbor hostility or animosity towards him today are not true Muslims. This group should not be regarded as part  of the Prophet’s (PBUH&HP) religion.

References:

1.  Al‑Irshad (2nd Volume - page 130)
2.  Sunan al-Termizi (6th volume – number 3775)
3.  Al-Kafi (1st Volume – page 452)

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*The Verse of Purification is the 33rd verse of Al-Aḥzāb in the Quran (33:33). The verse has special importance for Shia Muslims due to giving information about Ahl al-Bayt of Prophet Muhammad (PBUH&HP). Shias reportedly believe it to designate the "Ahl al-Bayt" being infallible.

When facing a question like this, you may find a group of people who try to justify that Islam is not a religion of peace. They usually refer to terrorist attacks by pseudo-Muslims and conclude that Islam is not a peaceful religion. Peace in Islam is a value and an ultimate goal of life; may it be personal, social or worldwide.

But let’s see what is Islam’s viewpoint about war and if it approves terrorism.

What Do We Mean by Peace in Islam?

Before discussing the main topic of this article, we have to understand what peace in Islam means. According to Merriam Webster dictionary, “peace is a state of tranquility or quiet such as:

Freedom from Civil Disturbance
A state of security or order within a community provided for by law or custom.
Freedom from disquieting or oppressive thoughts or emotions 
Harmony in personal relations.” [1]

Therefore, there are two types of peace defined above; social and individual. Islam not only talks about individual peace, but also all of its rules are based on logic to shape a peaceful society. In this article, we would focus on social aspects of peace in Islam, either within one country or on what goes on between different countries.

Peace in Islam

Allah emphasizes in the Quran that Prophet Muhammad (PBUH&HP) is a mercy towards all human beings: “We did not send you but as a mercy to all the nations” (21: 107). It can be understood from this verse that a worldwide mercy, peace, and tranquility is the goal of sending Prophet Muhammad (PBUH) with the religion of Islam.

Imam Ali (AS) in his letter to Malik al-Ashtar (his appointed commander in another country) wrote: “Develop in your heart the feeling of love for your people and let it be the source of kindliness and blessing to them. Do not behave with them like a barbarian, and do not appropriate to yourself that which belongs to them. Remember that the citizens of the state are of two categories. They are either your brethren in religion or your brethren in kind. They are subject to infirmities and liable to commit mistakes.”  [2]

He specifically notes that we should be tolerant of people who have no bad deeds against Muslims and the religion of Islam.

Are Muslims Peaceful towards Everyone?

In social relations The Quran defines Muslims as moderate people; “Muhammad, the Apostle of Allah, and those who are with him are hard against the faithless and merciful amongst themselves. “ (48:29)

By referring to the above verse and by going through its interpretations we find out that “Muslims should be harsh on infidels. Who are these infidels? Muslims should not be harsh on anyone who does not believe in Islam. They should behave kindly towards those who are not opposed to them, who do not plot against them, and who do not seek to wipe out their nations - even if they follow other faiths.” While at the same time “Muslims should be harsh on those who fight against Islam and their identity, nationality, country, independence, honor, dignity, traditions, culture, and values.” [3] Therefore, it is completely rational for Muslims to defend themselves while their values are being attacked, and it has no contradiction with their peaceful nature.

Does Islam Allow Terrorist Attacks?

In recent years we have seen different terrorist groups such as Taliban, Al-Qaida or ISIS, who under the name of Islam, have committed terrorist attacks in different countries. They refer to verses of the Quran that are about the holy struggle (Jihad) and use those verses as a permission for their terrorist acts.

However, their interpretations of the verses of the holy struggle (Jihad) are not correct. The fact is that war is prohibited in Islam, and Muslims are not allowed to start a war against other countries for the sake of conquest or even for spreading the religion of Islam. Jihad is allowed for Muslims only if:

They are attacked by other countries, and their lives and properties are at risk.
If other Muslim territories are under attack by oppressive governments.
If other powers attack Muslim territories to annihilate Muslims or their religion.

“In the holy struggle (Jihad), violating or infringing on others' rights is not allowed. Killing other people under baseless pretexts is not part of the holy struggle (jihad). Neither is killing those who are not Muslims. Such acts are not allowed in the holy struggle (Jihad). Not all those who believe in religions other than Islam should be treated with harshness. Rather, only those who are opposed to Islam, your independence and territorial integrity, and Islamic culture, identity, and values should be treated with harshness. If carried out under these conditions, the holy struggle (Jihad) is considered as a divine order and will bring about glory to nations.” [4]

It is only under these conditions that Muslims are allowed to fight against the oppressors. And even when they are allowed to defend themselves and enter the war, they have to make sure to follow the rules of war. They are not allowed to kill the children or elderly of the infidels, or to poison the cities of the infidels. [5]

They have to tolerate the refugees, and if they betray them, they will face punishment [6]. Also, they should observe the rights of the captives of war [7]:

“Allah does not forbid you from dealing with kindness and justice with those [polytheists] who did not make war against you on account of religion and did not expel you from your homes. Indeed Allah loves the just. Allah forbids you only regarding those who made war against you on account of religion and expelled you from your homes and supported [the polytheists of Makkah] in your expulsion, that you make friends with them, and whoever makes friends with them—it is they who are the wrongdoers.” (60: 8-9)

Islam Is a Peaceful Religion, not a Passive One

In conclusion, Islam is a religion of peace for Muslim people and peaceful people. It is not a passive religion to sit and watch all the cruel things that are happening in the world and smile at it. Islam is the life map for those who wish to reach human perfection which is only achieved by obeying all of its rulings. No matter you call it Islam or something else, but every sane human being, by studying The Quran and searching about Islam, will understand that Islamic rules have been designed to make the society a safe place for human growth.

References:

1. peace
2. Malik Ashtar richest treasure
3. view of Jihad
4. ibid
5. Mafatih al-hayat, p. 318
6. Mafatih al-hayat, pp. 419- 20
7. Mafatih al-hayat, p. 423