The main story of Umar’s conversion goes like this: he was sitting in a congregation with the Quraish, when Abu Jahal began his rant against the prophet. And eventually Abu Jahal said, ‘Who will finally rid us of this man? By Allah anyone who succeeds in doing it, I promise him 100 camels – red and black – and I'll also add 100 pouches of silver.’ Now this was a huge sum of money, and so Umar decided that he would be the one to finally assassinate the prophet. And so he unsheathed his sword and began hunting through the streets of Mecca. Eventually, he passed by Nu’aym ibn Abdullah (RA), who was a new Muslim who had not told anybody about his conversion. And Nu’aym asked Umar where he was going, to which Umar replied, ‘I am going to kill Muhammad.’ At this, Nu’aym began panicking, and said, ‘Have you lost your mind, O Umar? Do you really think the Banu Abd Manaaf will allow you to live after you kill one of their own? And if you really want to do something, go back and fix your own family first.’
‘What do you mean, fix my own family?’
‘Don’t you know? Your own sister and your own brother in law have accepted Islam.’ Now, Nu’aym just wanted to get Umar off of the back of the prophet, and he did not think that he would harm his own sister; however this was a personal insult for Umar. And so he became furious, and began marching to the house of Fatimah bint Al-Khattab’s (RA) house. And as he approached, he heard the recitation of the Quran. Now every new convert to Islam had been assigned a teacher, and the teacher assigned to Fatimah was Khabbab ibn Al-Aratt (RA), who we know as being one of the early slave converts to Islam. As well as them Fatimah’s husband was also present, and he was Saeed ibn Zaid (RA) – son of Zaid ibn Amr ibn Nufayl who as we know was one the 4 Hunafaa mentioned in the Quran, the one who the prophet said would be raised as his own Ummah on the day of Judgement. So Khabbab was teaching the Quran to Fatimah, and Umar heard this recitation as he approached the house. And when he banged on the door, he heard the scurrying sounds of Khabbab being hidden in the closet, and Fatimah hiding the parchment of the Quran under her skirt. And so he burst in, and demanded to know what it was he had heard.
At first, Fatimah denied that they had been doing anything, but Umar cut her off and said,’ By Allah, I know what I heard. And I know now that the both of you have accepted Islam.’ Now Umar had become madly angry, and so when Fatimah and Saeed began to deny his accusation, he took a step forward to punch his brother-in-law. And when he took this step, Fatimah stood up to try and stop him and the blow landed on her instead, and her lip burst open with blood. When this happened Fatimah and Saeed became defiant, and admitted to Umar that they had accepted Islam and were following the prophet Muhammad ﷺ, and that he could do as he pleased to them but they would not stop. Now, when Umar saw the blood and the determination of his sister and brother-in-law, his heart mellowed. And he asked, ‘Let me see what you are reading.’ But Fatimah did not allow him to read immediately, and told him that he had to purify himself first. And so first Umar went and did ghusl, before coming back and reading Surah Taha. And it was there that Islam fully entered Umar ibn Al-Khattab’s (RA) heart, and he committed to becoming a Muslim.
And so Saeed took Umar to the house of Al-Arkam (RA), where the prophet was at the time. And Umar still had the sword in his hand, so when he went and banged on the door of the house a sahaba stood up to go see who it was and found Umar standing there holding a sword. And he came back trembling, and told Muhammad ﷺ, ‘O Rasulallah, Umar ibn Al-Khattab is outside with a sword in his hand!’ So Hamza (RA), who was also present, said, ‘Let him in, for if Allah wants good, he is going to accept Islam. And if Allah wants other than this, then the very sword that he is holding is going to be the end of him.’ And so some sahabi went to the door and escorted Umar inside, and he came in and he sat down in front of the prophet.
Now, the night before, Muhammad ﷺ had actually made a du’a to Allah. And he had asked, ‘O Allah, bring glory to Islam with one of these two men who is the more beloved to you, either Abu Jahal or Umar ibn Al-Khattab.’ And so when Umar turned up at the door to the house of Al-Arkam, he knew that he was there to convert. But still, when Umar sat down the prophet held onto his collar and dragged him closer to himself. And he asked, ‘O ibn Al-Khattab, why are you here? By Allah, if you continue in this path then He will destroy you with a punishment.’
And Umar responded, ‘O Rasulallah, I came to accept Islam and testify to the truth.’ And it was then that the prophet himself did takbir, so loud that everyone in the house also knew that Umar had converted. And when this had happened, the Muslims – about 40 of them –marched onto the Kahbah for the first time, in two rows headed by Umar and Hamza (RA) to pray a public jamma’ in the haram. Before this, the Muslims could not pray in public for fear of persecution and interference. However now, with the conversion of the two huge figures of Umar and Hamza (RA), no would dare harm them. And this truly was a game changing moment for Islam. And it was here that the prophet gave the title Al-Farooq to Umar (RA) – meaning the one who divides good from evil – because he was the one who allowed the truth to come out of hiding and brought great izzah to Islam.
What do we learn from this? The main moral lesson to gain is to never declare someone as unable to change, for example when Laila told her husband about her how Umar ibn Al-Khattab softened and made du’a for her when she was packing for Abyssinia, and Aamir ibn Rabiya notoriously declared, ‘By Allah, the donkeys of his father’s house will accept Islam before he does.’ This, of course, was quite ironic, because despite how much of an enemy Umar (RA) was against the Muslims, and how much it seemed like he would never ever accept Islam, he went on to become the greatest expansionist to the Muslim cause ever – literally quadrupling the size of the conquest – and indeed, his khilafah was the pinnacle of the political power of the Muslim Ummah. And so when he was about to pass away, ibn Masud said of him, ‘We have ever remained in izzah, ever since Umar converted to Islam.’ And this shows the plan of Allah, that no matter what you may think of a person, Allah guides to Islam whoever he wills and whoever has sincerity in his heart.
Dr.Yasir Qadhi’s Seerah of The Prophet Muhammad (PBUH) 018
https://www.youtube.com/watch?v=q2bsjom_y8o