Allah (God) commanded both Musa A (Moses) and Harun A (Aaron) to go to Fir’awn (Pharaoh), the king of Misr (Egypt) who called himself god, to liberate the children of Isra’il.
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“So go you both [Musa (Moses) and Harun (Aaron)] to him [Fir’awn (Pharaoh)], and say: ‘Verily, we are Messengers of your Lord, so let the children of Isra’il go with us, and torment them not: indeed we have come with a sign from your Lord! And peace will be upon him who follows the guidance!
Surah (Chapter) Ta-Ha  The Qur-an 20:47

Allah (God) ordered then to talk gently and nicely to Fir’awn (Pharaoh), and assured them of His help and support to them. Fir’awn (Pharaoh) initially took both brothers as magicians. They countered the magic of Fir’awn’s (Pharaoh) biggest magicians and subdued them completely. That scared Fir’awn’s (Pharaoh), who amidst confusion, allowed them to leave Musa A (Moses) took his followers, the children of Isra’il (Israel), away from the oppression and torture of Fir’awn (Pharaoh). Fir’awn (Pharaoh) took his well-equipped army to chase the hapless people. Musa A (Moses) and his followers reached the sea, a place from where they could not go any further. With the mighty army of Fir’awn (Pharaoh) chasing them, they knew that their end was not too far.

Musa A (Moses) prayed Allah (God) for help, who told him to strike the sea with his staff to make way through it for his people.

And indeed We revealed to Musa (Moses) (saying): “Travel by night with Ibadi (My slaves) and strike a dry path for them in the sea, fearing neither to be overtaken [by Fir’awn (Pharaoh)] nor being afraid of drowning in the sea).”
Surah (Chapter) Ta-Ha  The Qur-an 20:77

Allah (God) showered His Mercy upon Musa A (Moses) and his followers by parting the sea when Musa A (Moses) struck it with his staff. He and the children of Isra’il (Israel) safely crossed the sea. In the meantime, Fir’awn (Pharaoh) and his army had also reached the spot. They were startled by the sight of the parted sea and a dry path on sea-bed. Following Musa A (Moses) and his followers, they also tried to cross the sea. When Fir’awn (Pharaoh) and his army came in the middle of the sea, it returned to its normal position. The waves swallowed Fir’awn (Pharaoh) and his entire army. By the Grace of Allah (God) Musa A (Moses) delivered his people to safety.


And (remember) when We delivered you from Fir’awn’s (Pharaoh) people, who were afflicting you with a horrible torment, killing your sons and sparing your women, and therein was a mighty trial from your Lord.
Surah (Chapter) Al-Baqarah (The Cow) The Qur-an 2:49

And (remember) when We separated the sea for you and saved you and drowned Fir’awn’s (Pharaoh) people while you were looking (at them, when the sea-water covered them).
Surah (Chapter) Al-Baqarah (The Cow) The Qur-an 2:50

Their caravan continued traveling till they reached Jabl (Mount) Tur. After camping there for some time, Musa A (Moses) decided to ascend Jabl (Mount) Tur to seek further guidance from Allah (God).

Musa A (Moses) asked his brother Harun A (Aaron) to look after the children of Isra’il (Israel) in his absence and to provide continuity to his mission of propagating the Message of Allah (God) among them. Musa A (Moses) asked for help from Allah (God) before leaving.

“And appoint me a helper from my family,


“Harun (Aaron), my brother.

“Increase my strength with him,


And let him share my task (of conveying Allah’s Message and Prophethood),
Surah (Chapter) Maryam (Mary) The Qur-an 20:29-32

Allah (God) granted the wish of Musa (Moses).

(Allah) said: “You are granted your request, O Musa (Moses)!
Surah (Chapter) Maryam (Mary) The Qur-an 20:36

Musa A (Moses) told his brother Harun A (Aaron) to continue his work.

And We appointed for Musa (Moses) thirty nights and added (to the period) ten (more), and he completed the term, appointed by his Lord, of forty nights. And Musa (Moses) said to his brother Harun (Aaron): “Replace me among my people, act in the Right Way (by ordering people to obey Allah and to worship Him Alone) and follow not the way of the Mufsidun (mischief-makers).”
Surah (Chapter) Al- A’raf (The Heights) The Qur-an 7:142

Musa A (Moses) remained at the Jabl (Mount) Tur for forty days, where he achieved the unique distinction of being directly addressed by Allah (God).

(Allah) said: “O Musa (Moses) I have chosen you above men by My Messages, and by My speaking (to you). So hold that which I have given you and be of the grateful.”
Surah (Chapter) Al-A’raf (The Heights) The Qur-an 7:144

The people of Musa A (Moses) did not expect him to stay at Jabl (Mount) Tur for so long and they became restless. They were worried and concerned about his welfare. Samiri, one of the followers of Musa A (Moses), took advantage of the situation and misled the Children of Isra’il (Israel). He started rumors that Musa A (Moses) must have met with an accident at the mountain. He made them to believe that Musa A (Moses) had wrongly told them that he was going up the mountain to seek Divine Guidance from his God.

Harun A (Aaron) tried his best to keep them obedient to Allah (God) and not worship that gold statue of calf, but the children of Isra’il (Israel) did not listen to him. They threatened to kill him if he stopped them from worshipping their golden calf.

And Harun (Aaron) indeed had said to them beforehand: O my people! You are being tried in this, and verily, your Lord is (Allah) the Most Gracious, so follow me and obey my order.”
Surah (Chapter) Ta-Ha  The Qur-an 20:90

Under the evil influence of Samiri, they forgot the Message of Tawhid [Oneness of Allah (God)] taught to them by Musa A (Moses). The children of Isra’il (Israel) collected golden ornaments from their families and made a golden calf from it and began worshipping that.

And the people of Musa (Moses) made in his absence, out of their ornaments, the image of a calf (for worship). It had a sound (as if it was mooing). Did they not see that it could neither speak to them nor guide them to the way? They took it (for worship) and they were Zalimun (wrong-doers).
Surah (Chapter) Al-A’raf (The Heights) The Qur-an 7:148

Musa A (Moses) returned from Jabl (Mount) Tur after receiving Guidance from Allah (God). On his return Musa A (Moses) was very upset and angry to find his people in the clutches of evil. He also directed his anger at his brother Harun A (Aaron) by dragging him by holding his hair, for his failure to discharge his duties properly.

And when Musa (Moses) returned to his people, angry and grieved, he said: “What an evil thing is that which you have done (i.e. worshipping the calf) during my absence. Did you hasten and go ahead as regards the matter of your Lord (you left His worship)?” And he threw down the Tablets and seized his brother by (the hair of) his head and dragged him towards him. Harun (Aaron) said: “O son of my mother! Indeed the people judged me weak and were about to kill me, so make not the enemies rejoice over me, nor put me amongst the people who are Zalimun (wrong-doers).”
Surah (Chapter) Al-A’raf (The Heights) The Qur-an 7:150

After listening about the entire episode from his brother Harun A (Aaron), Musa A (Moses) realized that his brother was not involved in that incidence. He prayed to Allah (God) to forgive his brother Harun A (Aaron), because he did not have any role in causing the children of Isra’il (Israel) stray away from the Right Path.


Musa (Moses) said: “O my Lord! Forgive me and my brother, and admit us intoYour Mercy, for You are the Most Merciful of those who show mercy.”
Surah (Chapter) Al-A’raf (The Heights) The Qur-an 7:151

To the contrary of the Holy Qur-an, the Torat (Torah) holds Harun A (Aaron) responsible for the calf worshipping. 
(Exodus 32:1-6).

The Qur-an exonerates him from this charge and holds only Samiri wholly responsible for the Shirk (Polytheism).

Harun A (Aaron) assisted Musa A (Moses) all his life and died at a place called Tih three years before the death of Musa A (Moses).

One Harun (Aaron) is mentioned in Ayah (Verse) 28 of Surah (Chapter) Maryam (Mary), as brother of Maryam (Mary). This Harun (Aaron) was another pious person from the time of Maryam (Mary) and should not to be confused with Harun A (Aaron), the brother of Musa A (Moses).
19:28 from the translation of the Holy Qur-an by Taqui ud Din Hilali and Muhsin Khan, , Page 405, 1420 AH edition published by King Fahd complex for the printing of the holy Qur’an, Madinah, KSA.

Harun A (Aaron) is mentioned by name in the Holy Qur-an in the following Ayat (Verses): (2: 248, 4:163, 6:84, 7:122 and 142, 10:75, 19:28 and 53, 20:30, 70, 90 and 92, 21:48, 23:45, 25:35, 26:13 and 48, 28:34, 37:114 and 120). His storey is spread in many more Ayat (Verses) throughout the Holy Qur-an.