Hazrat Bilal (Radhiallahu Anhu / May God be pleased with him) or Bilal Ibn Rabah and he sometimes also known as "Bilal al-Habashi" or "Bilal the Ethiopian", the first Muezzin of Islam, originally was a black slave from Ethiopia. Hazrat Bilal (ra) was one of the most trusted and loyal companion (Sahabi E Rasool) of our Holy Prophet Muhammad (saw) after converted to Islam.
Hazrat Bilal (Radhiallahu Anhu) is very lovingly remembered by Muslims around the world as one of the earliest great African Muslim. He was born in a village in a mountainous place in Western Arabia. Bilal's father was called Rebah and his mother was known as Hamamah. They had come to Arabia as slaves from Ethiopia. The father and mother were slaves of Umayyah ibn Khalaf ibn Safwan, a rich man from the tribe of Quraish. Bilal was therefore born in slavery and served as a housekeeper.
Among the slaves from Africa, Hazrat Bilal (ra) was the first to accept Islam. He had a strong faith in Allah (SWT) and a great love for our Holy Prophet Muhammad (saw). He had a pure character. Soon after converting to Islam he earned high respect of our Holy Prophet Muhammad (saw). Holy Prophet Muhammad (saw) liked Hazrat Bilal's sweet voice and made him the first Muazzin of Islam - The Caller to the Prayers.
Note: Muezzin or Muazzin is a chosen person at the mosque who leads the call (Adhan) to Friday service and the five daily prayers (Salat).
Following is the moral story of Islam's First Muezzin, Hazrat Bilal's conversion to Islam
The other day, when he came back from the desert, the signs of tiredness were seen on his face. The black man put his knapsack down and wiped the beads of perspiration from his forehead. The air was filled with dust churned up by the baaing sheep running towards the fold. The black man said to himself, "Now, perhaps I can take a rest for a while."
Since morning he had grazed the sheep under the hot sunshine of the Arabian desert and in the afternoon had decided to rest a few minutes, but he could not. The heat of the desert sand and sun would not permit sleep.
He placed the sheep in the fold and went to the water well. Just as he was about to wash his face with the cool water, he heard loud shouts, shouts of his Master Umayyah ibn Khalaf ibn Safwan (Was a leading member of the Quraish and head of the of Bani Jumah) and other people talking. Surely, something important has happened which caused Master Umayyah ibn Khalaf to shout that way!
Although Hazrat Bilal (Radhiallahu Anhu) was from Abyssinia (Ethiopia), but he lived in Makkah. When Bilal Ibn Rabah was sold to Master Umayyah ibn Khalaf, he was only a small boy. Master Umayyah ibn Khalaf always reminded him, "I am your owner, and you are my slave, you must obey me because your god has been made from wood and mine is from gold. This is the god's will." The shouting, cursing voice always made unpleasant noise in his ears.
Hazrat Bilal (ra) washed his face, took his knapsack and started towards his room. His room was dark, four walls in the basement of the big, aristocratic house. Bilal al-Habashi had not reached his room yet when he heard the shouts of his Master Umayyah ibn Khalaf raised again.
The shouts continued. Hazrat Bilal (ra) wanted to know what was going on, but he was afraid of getting close enough to the Master's room to hear what Master Umayyah ibn Khalaf was saying and why he was so angry. Yet, he was irresistibly drawn toward the room. Quietly, he stood at the door. Carefully, he listened to the talk, which continued, with only occasional shouts from his Master Umayyah ibn Khalaf. He recognized the voices as those of the aristocrats of Makkah. The voice of Umayyah ibn Khalaf, who was more nervous than the others, was raised again.
Umayyah ibn Khalaf spoke with indignation, "We must not let Mohammad freely disturb the city. Mohammad treated our idols with disrespect." Mohammad says, "There is only one God and everybody must worship him." "Do you know what this means? It means that I, Umayyah ibn Khalaf, the noble person of Makkah and Bilal al-Habashi, the ignorant black slave must have the same god ... Is that possible?"
At the same time, another aristocrat interrupted Umayyah ibn Khalaf's speech and said, "Our misfortune is too great because everybody knows him. Mohammad is well-known for truthfulness, innocence and trustworthiness."
Umayyah ibn Khalaf paused a moment and then said, "so we are compelled to say to people Mohammad has become mad (Majnoon)."
The others admired the thing, which Umayyah ibn Khalaf suggested. All Masters accepted this suggestion and the meeting ended. They all got up to go to their homes, but before they came out of the room, Bilal al-Habashi had gone to his room.
Bilal Ibn Rabah's room seemed to him darker and smaller than ever. Umayyah ibn Khalaf's words did not bring tranquility to him for a moment. He thought of the prophet of God and ... "Do people believe the aristocrat's words?" he asked himself. No ... No ... They would never accept that. Mohammad (peace be upon him) is the most innocent, trustworthy and most truthful man in Makkah. Everybody knows him. When he says there is only one God and these idols are not god, he certainly tells the truth. But why were only the aristocrats and Masters afraid of Mohammad's religion and his God?
That night Hazrat Bilal (Radhiallahu Anhu) thought much and he found out so many mysteries and could not sleep until late.