Abul Fida:
When Rasool was 40, he received Allah’s command to declare his Risalat (Be’that). His wife, Lady Khadija was the first person to accept Islam. According to an authentic hadith of Rasool, there are many men who are perfect in Eeman but there are only 4 women who are perfect, and the four are: (1) Aasia, wife of Fir’oun; (2) Mariam bint Imran; (3) Khadija bint Khwailad; and (4) Fatima bint Muhammad.
The following books, among many others, state that Ali ibn Abi Talib was the first among men to accept Islam: Seerah of Ibn Hisham; Kitab al-isaba of Ibn Hajar; Isti’yab of Ibn Abdul Bar Maliki.
ahlulbayth 