He immediately changed his direction from Arqam's house to...

He immediately changed his direction from Arqam's house to her house to investigate the allegation. In reply to his questions, she gave a discreet but evasive answer. Ibn Ishaq Umar came to the door (of the house of his sister) as Khabbab (a companion of the Prophet) was studying under her guidance the Sura Taha and also “When the Sun is Overthrown” (81:1). The polytheists used to call this reading “rubbish”.

When Umar came in, his sister saw that he meant mischief and hid the sheets from which they were reading. Khabbab slipped away into the house. Umar asked what was the gibberish he had heard, to which she answered that it was merely conversation between them...” (The Life of the Messenger of God) Umar exploded in wrath at what he believed to be a prevarication, and struck his sister in her face. The blow caused her mouth to bleed. He was going to strike again but the sight of blood made him pause.

He suddenly appeared to relent, and then in a changed tone asked her to show him what she was reading. She sensed a change in him but said: “You are an unclean idolater, and I cannot allow you to touch the Word of God.” Umar immediately went away, washed himself, returned to his sister's home, read the text of Qur'an, and then went to the house of Arqam where he formally accepted Islam.

Sir William Muir says that Umar's conversion to Islam took place at the close of the sixth year of the Prophet's mission. He adds the following footnote: It (Umar's conversion) occurred in Dhul Hijjah the last month of the year. The believers are said now to have amounted in all to 40 men and ten women; or by other accounts, to 45 men and eleven women. (The Life of Mohammed, 1877, p. 95) Umar was about 35 years old when he became a Muslim.

Muhammad Husayn Haykal At that time, (when he was converted to Islam) Umar ibn al Khattab was a mature man of thirty to thirty-five years of age. (The Life of Muhammad) Many Muslims claim that with Umar's conversion, Islam recruited new strength, and Muslims were now emboldened to dare the pagans.

They could, according to these claims, now come out of their places of hiding, and pray openly in the precincts of Kaaba, or rather, it was Umar himself who brought them out of their hiding places, and they were not now afraid of Abu Jahl or of anyone else. Muhammad Husayn Haykal The Muslims who returned from Abyssinia did so for two reasons. First, Umar ibn al Khattab was converted to Islam shortly after their emigration.