In Islam, there are some ceremonies and occasions which are held all around the world among Muslims. They all have religious backgrounds and are mostly referred to in the holy Quran. Muslim nations have been commemorating them in the course of history. Here we are going to have a glance at the most significant Islamic occasions based on the Lunar Calendar.

6 Major  Islamic Occasions 

1.10th of Muharram: Martyrdom of Imam Hussain (AS)

The month of Muharram is the first month of the year in the lunar calendar. On the tenth day of this month, Hussain Ibn Ali (AS), the grandson of Prophet Muhammad (PBUH&HP), and his companions were brutally martyred, and their women and children were taken captive by the caliph of the time, Yazid ibn. Muawyah. Their story has been the source of inspiration for many new converts. 

2. 20th of Safar: The Day of Arbaeen

Arbaeen is the Arabic word for forty, and it marks the 20th of Safar, the fortieth day after Imam Hussain's (AS) martyrdom on the day of Ashura, who was martyred in the event of Karbala along with his companions in the cruelest and most inhumane way possible. 

According to some historical accounts [2], some of the members of Imam Hussain's (AS) family after being released from the bondage of Yazid's forces returned to Karbala from Sham (today's Damascus) to visit Imam Hussain's (AS) grave. Also, some believe that Imam Hussain's (AS) head, which was taken to Sham by Yazid's army was brought back to Karbala on this day and buried with his body [3] & [4]. 

Every year, a few days before this day, a vast number of people from all over the world, Muslims or even non-Muslims, gather in Iraq to take part in a symbolic walk, to revive the teachings of Imam Hussain (AS) and commemorate his sacrifice in the way of Allah and humanity. 

3. 17th of Rabi al-Avval: Prophet Muhammad's (PBUH&HP) Birthday

There is a disagreement concerning the exact date of Prophet Muhammad's (PBUH&HP) birthday. Some believe it occurred on the 12th of Rabi al-Avval, while others consider it to be on the 17th of Rabi al-Avval, the third month in the Islamic calendar. Prophet Muhammad (PBUH&HP) was born in Mecca. All Muslims around the world celebrate his birthday and regard it as one of the important Islamic occasions. On this day, Muslims feed the needy, pray and recite the Quran, commemorate Prophet Muhammad (PBUH&HP), and his challenges to deliver the messages of Allah to human beings.

4. 1st of Shawwal: Eid al-Fitr

The first day of the month of Shawwal, the tenth month of the Islamic calendar, is called Eid al-Fitr. After fasting for one month, during the month of Ramadan, remembering, worshipping Allah and trying to do fewer sins beside not eating and drinking from before the Call for Fajr prayer to after the Call for Magrib prayer, Muslims celebrate the first day of the month of Shawwal, for their success in submitting to Allah's command. They perform the Eid prayer first; then, they hold a feast inviting their loved ones, wear their best clothes, and visit their friends and family. The culture of feasting might be different in different Islamic communities, but one thing is for sure; no one is allowed to fast on this exceptional day. Allah also obliges Muslims to share their blessings and happiness with the needy with the money they donate to them. 

5. 10th of Dhu'l-Hijjah: Eid al-Adha

Eid al-Adha is one of the most significant Islamic occasions. Some of the most important events of this Abrahamic religion happened on this day. On this Eid, similar to Eid al-Fitr, Muslims are not allowed to fast. The first is the sacrifice of Ishmael by his father, Abraham, for the sake of Allah. When Abraham and his son both surrendered, and he was ready to behead his son, Allah sent a ram and asked Abraham to kill that instead.

"So when they had both surrendered [to Allah's will], and he had laid him down on his forehead, We called out to him, 'O Abraham! You have indeed fulfilled your vision! Thus indeed do We reward the virtuous! This was indeed a manifest test. Then We ransomed him with a great sacrifice, and left for him a good name in posterity." (37: 103-108)

This day is also the last day of Hajj rituals, in which Muslims shall sacrifice an animal to feed the needy Muslims. On this day, those who attended Hajj have performed all their Hajj rituals, and with the great assistance of Allah, all their sins are wiped away, and Allah accepts their good deeds and repentance.

Many Muslims celebrate this day. They sacrifice an animal to feed the needy, even if they have not attended Hajj. If they do not have enough money to buy a sheep, they do other things and feed the destitute in different ways. This sacrifice is an expression of generosity and obedience to the commands of Allah. This Eid also reminds humankind of the characteristics, such as envy, rage, dishonesty, etc., they have to symbolically sacrifice in themselves to become the better version of themselves and be worthy of being Allah's best creation. 

5. 18th of Dhu'l-Hijjah: Eid al-Ghadir

This Islamic occasion was a day in the last Hajj pilgrimage (Hajjat al-Vida'a) of Prophet Muhammad (PBUH&HP). When he was going back to Medina with all his companions and other pilgrims, he gathered everyone around a place called Ghadir and announced these words in which he appointed Imam Ali b. Abi Talib (AS) as his caliph and the Imam after himself following a direct order from Allah [i]:

"Whomsoever, I am his leader (Mawla), Ali (AS) is also his leader (Mawla). O' Allah! Love those who love him (Ali (AS)) and oppose those who oppose him" [1]

This is another important day in the Muslim calendar. On this day, Muslims can fast and again feed the needy, as an essential part of Islamic culture. 

These are the most significant and most celebrated Islamic occasions. As one can see, feeding others and praying to Allah are the essential things a Muslim should do to celebrate a feast, which reveals the importance of caring for others in Islam that results from the devotion to Allah.  

Notes: 
[i] Verse 67th of Surah al-Maedah known as Al-Tabligh Verse, and the third verse of the same chapter known as Al-Ikmal Verse. 

References:

1.  Ibn Athīr, Usd al-ghāba, vol. 3, p. 605; Kulaynī, al-Kāfī, vol. 1, p. 295; Balādhurī, Ansāb al-ashrāf, vol. 2, p. 110-111;
2.  Ibn Tawus, 'Ali b. Musa, Al-Luhuf 'ala qatla l-tufuf, Uswi, Qom, 1414 AH.
3.  Al-Biruni, Abu Rayhan, The Remaining Signs of Past Centuries, p.331.
4. Qazi al-Tabataii, Muhammad Ali, A Research on the first Arba'een of the Leader of Martyrs (Imam Hussain (AS)), vol.3, p.304.
    

If your right were taken away unfairly, what would be your reaction? Of course, you would stand up for your right and try to take it back or maybe fight for it. What if this reaction would make everything worse? What if you realize that your compromise, leads into the greater good of yourself or even the society? Fighting against injustice, sometimes, includes sacrifices, which goes beyond egotistic and individual desires. Depending on the situation, one might be made to compromise and sacrifice his/her right for the sake of his/her higher purpose, while having the power to take his/her right back. And this can only be done by a spiritually and mentally powerful person, such as Imam Hasan al-Mujtaba (AS), the first grandson of Prophet Muhammad (PBUH&HP). 

In what follows, we will review the life of this exceptional figure in the history of Islam. 

Birth and Lineage

Hasan ibn Ali (AS), known as Hasan al-Mujtaba (AS), was born on 15th of Ramadan, 1st of March, 625 A.D. in Medina. He was the first son of Imam Ali (AS) and Lady Fatima (AS), and the first grandson of Prophet Muhammad (PBUH&HP). His name, "Hasan," which means good or beautiful, and was chosen by his grandfather, the Prophet (PBUH&HP), for him, having no precedent in this name in the pre-Islamic history. 

Imam Hasan (AS) and Prophet Muhammad (PBUH&HP)

Imam Hasan (AS) was only seven years old when Prophet Muhammad (PBUH&HP) passed away. Prophet Muhammad (PBUH&HP) dearly loved him, and as it is narrated, he used to put Imam Hasan (AS) on his shoulders and said, "O' Allah! I love him, therefore, You love him, too." [1] In some instances, while Prophet Muhammad (PBUH&HP) was performing the congregational prayer in the mosque, Imam Hasan (AS), then a little boy, would go on Prophet Muhammad's (PBUH&HP) back while he was prostrating. In response, Prophet Muhammad (PBUH&HP) would kindly and patiently prolong his prostration, so that he would come down himself. Prophet Muhammad's (PBUH&HP) manner of treating his grandsons was, in fact, a model to his followers to treat their children respectfully and compassionately. 

His love and respect toward Imam Hasan (AS) are evident through the many narrations left by him about his grandson: "Surely, Hasan and Hussain are my two fragrant flowers from this world; he who loves me, should love them, too" [2], "Hasan is my son and dear to my heart, whoever hurt him, is like he's hurting me" [3], "Hasan and Hussain are the masters of the youth in paradise" [4]. It has also been narrated that Imam Hasan (AS) very much looked like Prophet Muhammad (PBUH&HP) in both appearance and personality [5]. Despite his young age, Imam Hasan (AS) was present in many significant incidents in Prophet Muhammad's (PBUH&HP) time.

The Short Period of Imam Hasan (AS)'s Caliphate 

After Imam Ali's (AS) tragic martyrdom in 661 A.D, many people in Iraq and the neighboring lands pledged allegiance to Imam Hasan (AS), as the most suitable person to be their Caliph succeeded by Imam Ali (AS). Nevertheless, soon after this pledge of allegiance, Mu'awiya b. Abi Sufyan [i] refused to respect people's choice and offended Imam Hasan's (AS) caliphate. He tried to incite people of Iraq by sending two spies who were captured and punished by Imam Hasan (AS) [6]. Finally, Mu'awiya provoked a rebellion in Syria against Imam Hasan (AS) and built an army to go into war with Imam (AS) in Iraq. It is reported that 60,000 soldiers or more accompanied Mu'awiya [7].

In this situation, Imam Hasan (AS) gathered an army of Kufa people to fight against them and defend the people. Some minor battles occurred between the two troops. Later, Imam Hasan (AS) joined the army of Kufa and gave a sermon to them, inviting them to unity and reconciliation rather than hatred and enmity. After this speech, people thought that Imam (AS) was after making peace with Mu'awiya and accused him of disbelief, attacked his tent, and left his side. Also, some of the heads of Imam Hasan's (AS) army, including "Ubayd Allah b. 'Abbas", the commander in chief of Imam Hasan's (AS) army, joined Mu'awiya's army with two-third of his army.  Before that, Mu'awiya had sent them letters and promised them high positions in his government and a considerable amount of money. This was followed by the letters of the chiefs of Iraqi tribes to Mu'awiya, expressing him their support.

All these incidents resulted in the significant physical weakening of Imam Hasan's (AS) army and losing their spirit, despite Imam Hasan's (AS) efforts to give them heart through his influential and alarming speeches. Yet the covert activities of Mu'awiya in Kufa, sending his forces undercover among people and spreading false accusations concerning Imam Hasan (AS), gradually broken Imam Hasan's (AS) army. Some even assassinated Imam Hasan (AS) and wounded him severely. 

Finally, pressing hard under the conspiracies of Mu'awiya and the weakness of people in fighting against injustice, which had disturbed the military balance between the two armies, Imam Hasan (AS) was made to accept a peace treaty and leave the caliphate to Mu'awiya [8]. Thus, the period of Imam Hasan's (AS) caliphate lasted between six to eight months.

The Peace Treaty between Imam Hasan (AS) and Mu'awiya 

According to historical accounts, "Mu'awiya sent a blank contract with his seal at the bottom for Imam al-Hasan (a) to write anything that he wished and thus he wrote, "In this peace treaty, al-Hasan b. 'Ali (a) establishes peace with Mu'awiya b. Abi Sufyan and leaves the government of the Muslims to him with the following conditions:

1. He observes the Book of God, the conduct of the Prophet (s), and the conduct of the righteous caliphs.
2. He appoints no one as the Caliph after himself; and after him, the Caliph should be elected by a council of Muslims.
3. Lives, property, and children of people should be safe everywhere.
4. Mu'awiya should not implicitly or explicitly plot against al-Hasan b. 'Ali or threaten any of his companions." [9] 

Under these conditions, Imam Hasan (AS) signed the peace treaty in 661 A.D. However, all of these conditions were later denied by Mu'awiya in his sermons and manners. "After the peace treaty, Imam (AS) gave a sermon and pointed to this issue that Mu'awiya challenged him over his rights and explained the reasons for his peace, which was to protect the lives of people and avoid bloodshed. After the treaty, Mu'awiya, too, gave a sermon at his first presence in Kufa. He broke his promises, saying that Imam (AS) had asked for peace and cursed Imam Ali (AS). Then, Imam Hasan (AS) explained about the peace treaty in a sermon and the proposal of Mu'awiya for it and answered to Mu'awiya's disrespect to his father." [10]

After this incident, Imam Hasan (AS) went back to Medina. While he was not a caliph anymore, he felt the responsibility to guide people in religion, science, and social and political issues. The signing of the peace treaty had made the situation very difficult for him. Some people criticized him, some of his old companions left his side, and severe political measures were taken against him. 

Imam Hasan (AS)'s Prominent Characteristics

Forbearance and Patience 

Imam Hasan's (AS) patience in the face of hardship becomes evident by having a glance at his life, which was full of challenges. Losing Prophet Muhammad (PBUH&HP) when he was only a child, losing his mother, lady Fatima (AS), bearing the difficulties at the time of his father's caliphate, following by his martyrdom most brutally, electing as a caliph by the people and then being abandoned by the same ones provoked by Mu'awiya, being forced to accept a peace treaty and giving up caliphate unfairly, was only some of these hardships. No doubt, without a strong personality resulted from a deep belief in Allah, Imam Hasan (AS) would not be able to bear these sufferings and challenges. 

Moreover, he presented forbearance even when he was directly insulted and never responded with anger. In an instance, "a Syrian man saw Imam Hasan (AS) and started cursing him. When he finished his insults, the Imam (AS) smiled, greeted him, and said, "It looks like you are a stranger in this city … If you need anything, we will fulfill your needs." The man was deeply impressed by the Imam's (AS) noble reaction; he started crying and recited the following verse: "God knows best with whom to place His message" (Quran 6:124), indicating that the Imam (AS) deserved to be a descendant of the Prophet (PBUH&HP)" [11]. 

Generosity 

Imam Hasan's (AS) life was full of instances, which revealed his immense generosity and selflessness. It is narrated that he had given away all his properties and wealth as a charity twice in his lifetime [12]. According to an account, a man in need came to Imam Hasan (AS). Imam (AS) asked him to write what he needed and give him the note. When Imam (AS) read his letter, he gave him twice more than what he had asked. One of the people who were present there said, "What a bounteous letter he wrote, O' son of the Prophet (PBUH&HP)!" Imam (AS) replied, "The letter had more bounty and blessing for us than him since it had made us among the generous ones. Don't you know that "generosity" is to give something to someone without being asked for, and what is given away after being asked, is paltry in return to that person's honor.  Perhaps the one who asked for something had spent a night full of stress and fear, not knowing if you reject him or make him happy with accepting to fulfill his request. Now he has come to you, his heart beating fearfully. If you, then, give him no more than what he had asked, you don't give away anything worthier than his honor, which he had broken for this request." [13] 

Imam Hasan's (AS) generosity was not limited to human beings, but all of Allah's creatures. In one account, a man saw Imam Hasan (AS) eating, giving a morsel of his food to a dog, and eating a morsel himself. The man who was surprised by this scene went closer to Imam Hasan (AS) and said, "Would you permit me to hit this dog with a stone and take him away from your food?" Imam (AS) replied, "Leave it alone! Since I feel ashamed of Allah al-Mighty if an alive animal looks into my face while I'm eating and I won't give it part of my food." [14]  

Imam Hasan (AS) found generosity and doing charity, not as a mere religious burden; instead, he gave away willingly and saw it as a chance bestowed to him by Allah to please Him. 

Humbleness toward the Poor

The grandson of Prophet Muhammad (PBUH&HP), following the footsteps of his grandfather, was highly observant of his manner toward the ones in need, being careful not to break their hearts or belittling them while helping them. It is reported in an account, "One day, he passed by a group of poor people who were eating pieces of bread. When they saw him, they invited him to eat with them. The Imam (AS) accepted their invitation and sat and ate with them and then invited all of them to his house and offered them food and clothes." [15]

Imam Hasan (AS) never felt superior to other people and treated everyone, regardless of their age or position, with the same respect and modesty. 

His Love for Allah  

All the above characteristics of Imam Hasan (AS) and many more is a reflection of his deep devotion and love toward Allah, the One and Only Creator. Imam Hasan (AS) was the perfect example of a true believer both in manner and words. He was famous for his sincere worship, long prayers, and his enthusiasm to go on a pilgrimage to Mecca on foot. He would say, "I would be embarrassed to meet my Lord without having walked toward His house." [16] 

His abiding faith had made him a strong and exemplary personality from whom any human being with a free soul can learn the lesson of humanity and love.   

His Martyrdom

According to some historical sources, After disregarding the conditions in the peace treaty, Mu'awiya conspired the assassination of Imam Hasan (AS) to secure the position of his son, Yazid, as his successor. To further his plan, he sent for Imam Hasan's (AS) wife and enticed her to poison her husband in return for money and marrying Yazid. Finally, she accepted his offer and fatally poisoned Imam Hasan (AS) [17]. He was martyred in the 15th of Ramadan of 50 (670 A.D.) and was buried in al-Baqi' cemetery in Medina. 

Notes:

[i] The first Umayyad caliph who ruled in Damascus after the Peace Treaty of Imam Hasan (AS).

References:

1. Ali ibn Abd-al-Malik al-Hindi, Kanz al-Ummal, Vol.16, p.262. 
2. Al-Tirmidhi, Sunan At-Tirmidhi, Vol.5, p.615. 
3. Qadi Nur Allah Shushtari, Ihqaq al-haqq, Vol.11, p.63. 
4. Muhammad b. 'Ali b. Shahrashub, Manaqib Al Abi Talib, Vol.3, p. 394. 
5. Muhammad Baqir al-Majlisi, Bihar al-Anwar, Vol.43, p.338. 
6.  Al-Shaykh al-Mufid, Kitab al-Irshad, Translated by I.K.A Howard, Published by Tahrike Tarsile Qur'an. p.350. 
7.  Al-Sharif al-Qarashi, Baqir, The life of Imam al-Hasan al-Mujtaba (a), translated by Jasim al-Rasheed, Qom, Ansariyan Publications. p.334-335. 
8.  Muhammad ibn Jarir al-Tabari, History of the Prophets and Kings, Vol.5, p.324. 
9.  Al-Baladhuri, Ahmad ibn Yahya. Ansab al-Ashraf, vol. 3, p. 41-42. 
10. Imam Hasan Mujtaba
11.  Baha' al-Din 'Ali b. 'Isa al-Irbili, Kashf al-ghumma fi ma'rifat al-a'imma, Vol.1, p.561. 
12. Ahmad b. Abi Ya'qub, Tarikh al-Ya'qubi, Vol.2, p.226. 
13.  Ahmad b. Muhammad b. Khalid al-Barqi, Al-Mahasin, p.55. 
14. Muhammad Baqir al-Majlisi, Bihar al-Anwar, Vol.43, p.352. 
15. ibid, p.319. 
16.  Muhammad b. 'Ali b. Shahrashub, Manaqib Al Abi Talib, Vol.4, p. 7. 
17.  Abū al-Qāsim Maḥmūd ibn Umar al-Zamakhsharī, Rabi al-Abrar wa nusus al-Akhbar, Vol.5, p.155-156.