Ammar ibn Yasir
During the first three years of his ministry, Muhammad preached Islam privately, mainly among his near relatives and close acquaintances. The first to believe him was his wife Khadijah, who was followed by Ali, his cousin, and Zayd ibn Harithah. Notable among the early converts were Abu Bakr, Uthman ibn Affan, Hamza ibn Abdul Muttalib, Sa'ad ibn Abi Waqqas, Abdullah ibn Masud, Arqam, Abu Dharr al-Ghifari, Ammar ibn Yasir and Bilal ibn Rabah. In the fourth year of his prophethood, according to Islamic belief, he was ordered by God to make public his propagation of this monotheistic faith (Quran ).