There is no doubt among us that after our dear Prophet Mohammad (PBUH&HP), our twelve Imams (AS) are the most important figures of our religion. On that account, today we want to get to know more about our first imam and the first male convert of the religion birth matter and conditions.

The faithless say, ‘You have not been sent [by Allah].’ Say, ‘Allah suffices as a witness between me and you, and he who possesses the knowledge of the Book’
The Holy Quran (13:43)

And among the people is he who sells his soul seeking the pleasure of Allah, and Allah is most kind to [His] servants
The Holy Quran (2:207)

If the two of you repent to Allah... for your hearts have certainly swerved, and if you back each other against him, then [know that] Allah is indeed his guardian, and his supporters are Gabriel, the righteous among the faithful and, thereafter, the angels...
The Holy Quran (66:4)

If we seek the true meaning of these three verses above of our holy book, they all seek Ali (AS) as their primary target and guide us to some aspects of his life. our dear imam has been implicitly described by The Quran many times that shows us His great importance in our religion.  
No one can fully describe the contributions of Imam Ali (AS) to his religion and the people and if anyone dares to do so, he can merely show a drop of the sea. That said we are about to speak about the first question that may occur to our mind: how was our first Imam born?

Birth of the Son of Kaaba, Ali b. Abi Talib

Thirty years after the “year of the elephant” (*) occurrence, in the 13th of Rajab (March 8), when Prophet Mohammad (PBUH&HP) was 30 years old, 10 years before our dear The Prophet (PBUH&HP) received the first revelation from the angel Gabriel and 23 years before the great migration of Muslims from Mecca to Medina.

At this time, our dear imam's pregnant mother (Fatima Daughter of Asad) was praying at Kaaba. She felt an immense amount of delivery pain that she fled to Kaaba from that pain. Suddenly the wall of Kaaba has moved apart and given shelter to her for 3 whole days. After these days, she came out of Kaaba with her dear son, our first imam, Ali b. Abi Talib (AS). Imam’s delivery was a great honor that happened to no one And after yet; walls moving apart, mother’s presence in the holy site of Islam, and the unique birth in Kaaba were all the signs of the greatness of son of Kaaba.
Fatima Daughter of Asad was the second woman that converted to Islam (after Prophet’s wife, Khadija” SA”). She had the honor of taking care of the Prophet (PBUH&HP) from the age of eight until his youth in her (Abu-Talib) house. Their relation was as much close that Prophet (PBUH&HP) called she “mother” So we can see the early strings of Prophet (PBUH&HP) calling Imam Ali (AS) his brother.

Shia point of view about Imam Ali (AS) birth:

1.Sheikh Mofid (died in 413th AH): our first imam, Ali b. Abi Talib (AS) was born on Friday the 13th of Rajab and thirty years after the year of the elephant in Mecca. No one ever has been born in Kaaba before and after him. His delivery was the great honor that God granted him to show his dignity over other men of his age.

2. Allamah Al-Hilli (died in 726th AH): Imam Ali (PBUH) was born on Friday the 13th of Rajab and thirty years after the occurrence of the year of the elephant. No one before and after him, was born in Kaaba at that time, The Prophet (PBUH&HP) was thirty years old.

Sunni point of view about Imam Ali (AS) birth:

Many of the Sunni scholars Believe that Imam’s birth routine was in Kaaba and some of them even think this matter exclusively was only for the Imam.

We will name some of them briefly and look at their point of view:

1. Al-Hakim al-Nishapuri (died in 658th lunar year): a lot of Consecutive narrations have pointed that Fatima bt. Asad have delivered Ali b. Abi Talib in the Kaaba.

2. Sibt ibn al-Jawzi Hanafi (died in 654th lunar year): It has been narrated that when Fatima bt. Asad was pregnant and doing tawaf around the Kaaba, she sensed an immense delivery pain that she fled to Kaaba from the pain; when suddenly Kaaba’s door got opened to her so she went into the Kaaba and gave birth to his child.

Poetry about imam Ali (AS) birth:

Syed Ismail Himayari (who died in 173th AH) was one of the greatest poets of Arabic literature. He wrote a poem about this unique birth:

His mother gave birth to him in God’s safe site; God’s house and masque was his birthplace

He was pure and noble; her mother, her child, and her birthplace too

In one of the darkest nights, he appeared with lunar purity

No child other than Amine’s child is honored like him

References:

1. Kitab al-Kafi (first Volume – page 452)
2. Kitab al-Irshad (first Volume – page 5)
3. I'lam al-Wara bi A'lam al-Huda (first Volume – page 306)
4. Bihar al-Anwar (35th Volume – page 182)
5. Description of Nahj al-Balagha (first Volume – page 6)
6. Manaqib Ale Abi Talib (third Volume – page 307)
7. Rawżat al-Vaeezin (page 81)

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* In that year, Kaaba invaded by faithless king Abraha and his great elephant army and ironically saved by Allah himself with an army of birds carrying small stones by their pecks that penetrate the elephant's body and skull and all of them got killed, and Kaaba was saved.

Eid al Adha (or Dhuha) is one of the greatest eids of Islam. It is a feast of love, sacrifice, and submission to the will of Allah (s.w.t). Celebrated on the 10th of Dhul Hijjah, the last month of the Islamic calendar, it is the time of the year where Muslims from all over the world gather for the annual ritual of Hajj and mark the end of Hajj by sacrificing a camel, a cow or a sheep. Those Muslims who could not make it for Hajj, sacrifice these animals and distribute the meat and other gifts among the poor, their family and friends. 

There are many recommended (not obligatory) rituals and practices to be performed on the day of Eid al Adha, some of them are as follows: 

-Doing Ghusl (ritual bath)
-Eid Prayer, either in a congregation or individually
-Reciting the Ziarat of Imam Husain (AS), the third infallible Imam
-Sacrificing either a camel, cow, or sheep. Sacrifice is obligatory for those performing Hajj and recommended for those not performing Hajj
-According to Islamic laws, it is forbidden to fast on this day

History of Eid al Adha 

Prophet Abraham (PBUH) was a true embodiment of the verse from the Holy Quran: “Do the people suppose that they will be let off because they say, ‘We have faith,’ and they will not be tested? Certainly, We tested those who were before them. So, Allah shall surely ascertain those who are truthful, and He shall surely ascertain the liars.” (29:2)

Prophet Abraham (PBUH) was a great Prophet of Allah (SWT) who is greatly celebrated in the Holy Quran. He is one of the Ulu –l-Azm (Arch) prophets. Allah (SWT) calls him his friend in the Holy Quran (4:125). The intended sacrifice of this holy prophet is greatly eulogized in the Holy Quran and the prophetic traditions. Abraham is especially famous for the numerous ways God tested him; especially the tough tests of leaving his wife Hagar and his firstborn son Ishmael (2:124) and bringing his son to a special place as an offering to God (37:100-113).

The story of Prophet Abraham sacrificing his son is mentioned in the Holy Quran as follows: 

“My Lord! Give me [an heir], one of the righteous.” So We gave him the good news of a forbearing son. When he was old enough to assist in his endeavor, he said, ‘My son! I see in dreams that I am sacrificing you. See what you think.’ He said, ‘Father! Do whatever you have been commanded. If Allah wishes, you will find me to be patient.’ 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 mission! 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: ‘Peace be to Abraham!’ Thus, do We reward the virtuous? He is indeed one of Our faithful servants.” (37:100-110)

The Holy Quran gives us a very clear picture of the incidents that unfolded with Prophet Abraham (PBUH). It tells us that Prophet Abraham (PBUH) prayed for a righteous heir and Allah (SWT) answered his prayers. But after a few years, Allah (SWT) orders his Prophet to sacrifice his only son and both Prophet Abraham (PBUH) and Prophet Ishmael (PBUH) agree to submit to the will of Allah (SWT). It was a test for Prophet Abraham (PBUH) as well as his son Prophet Ishmael (PBUH), who emerged victorious from this test. Thus, leaving a legacy of complete submission to the will of Allah (SWT), a submission that calls for sacrificing everything you have to gain the pleasure of your beloved creator. It is this humble and pure submission of Prophet Abraham (PBUH) that makes this great prophet a ‘good example’ for us. (60:4). 

The sacrifice of Prophet Abraham is not a fairy tale to be read to our children before going to sleep, it is a story that has the potential to make human beings build a lasting relationship with Allah (SWT). If we truly trust in Allah (SWT) and reach a position where we readily sacrifice everything in the way of Allah, we can proudly claim to be inheritors of the legacy of Abraham, a friend of Allah (SWT). But for us to reach that position we need to first ask ourselves: who is our Ishmael? Is it my child, my spouse, my property, wealth, job, position or my desires? 

References

1. Quran Translations, Ali Quli Qara’i
2. Recommended rituals and practices on the eve of Eid and the day of Eid: Dua for EID ul Adha Night and Day (duas.org) (these recommended acts can also be found in Mafatih Al-Jinan under the section of aamaal for Eid)
3. Exegesis of Surah Saaffat, Tafseer Nemuneh, Ayatollah Makarem Shirazi (Farsi)