Conversion of the Earliest Forerunners:
Ibn Ishaq said: Some scholars relate that whenever the time for prayer came, the Messenger of Allah—peace and blessings be upon him—would go out to the ravines of Mecca with ʿAli. There they would pray, and when evening arrived they would return. One day Abu Talib passed by them while they were praying and said to the Prophet, “My nephew, what is this?” He answered, “O Uncle, this is the religion of Allah, the religion of His angels and His messengers, the religion of Abraham. Allah has sent me with it as a messenger to humankind. You, O Uncle, are the one most deserving of my counsel and my invitation to guidance, and the one most entitled to answer me and support me.” Abu Talib replied, “My nephew, I cannot abandon the faith of my forefathers. Nevertheless, by Allah, nothing you dislike shall reach you for as long as I live.” He said nothing to ʿAli that would offend him, and it is claimed that he added, “He is only calling you to what is good, so follow him.”

Thereafter Zayd ibn Harithah, the freedman of the Messenger of Allah, embraced Islam; he was the first male slave to do so, and he prayed after ʿAli.

Hakim ibn Hizam had once returned from Syria with a number of slaves. Khadijah bint Khuwaylid visited him, and he said, “Choose whichever of these boys you like; he is yours.” She chose Zayd and took him. When the Prophet—peace and blessings be upon him—saw Zayd, he asked Hakim for him as a gift, and Hakim gave him. The Prophet then set Zayd free and adopted him before the revelation began. Later Zayd’s father, Harithah, arrived in distress, grieving for his son. The Prophet said to Zayd, “If you wish, stay with me, and if you wish, go with your father.” Zayd replied, “I will stay with you.” Hence he was known as Zayd ibn Muhammad until the verse was revealed, “Call them by [the names of] their fathers; that is more just in the sight of Allah” (Qur’an 33:5), whereupon he said, “I am Zayd ibn Harithah.”