The clarion call came to Bilal Habashi’s (raa) ears that a man, born of the noblest class in Mecca, who enjoyed exceeding popularity and commanded deep respect from the rank and file was preaching a staunch message of equality of all human beings. The message of the Rabb (lord) who makes no discrimination between the high and the low, the rich and the poor, The Arab and the non-Arab. He was spreading the message that there is only one God and everybody must worship him.
Like a flash of lightning, the thought had crossed Bilal’s (raa) mind, how could a man risk the loss of his popularity and reputation to liquidate class differences in order to put the master and slave equal unless he was the Truthful Messenger and the Prophet of the Creator.
So upon hearing the message of One God, Allah, and the equality of all human beings issued by the noblest personality of the most respectable family, Banu Hashim, Bilal (raa) at once made an affirmative response and declared the testament of faith, the Shahadah, "la ilaha ilallah Muhammadur rasulullah, the is no God but Allah and Muhammad (saws) is his messanger".