Bilal bin Rabah RA is one of the eminent Sahabah of the Prophet Muhammad SAW best known as the Prophet's muazzin (caller to prayer). Bilal RA was an Abyssinian slave of a disbeliever in Makkah. His conversion to Islam was, naturally, not liked by his master and he was, therefore, persecuted mercilessly. Ummayah bin Khalaf, who was amongst the worst enemies of Islam, would make him lie down on the burning sand at midday and would place a heavy stone on his chest, so that he could not even move a limb.
He would then say to him:
"Renounce Islam or swelter and die."
Even under these afflictions, Bilal RA would exclaim:
"Ahad... Ahad..." ( - "The One... The One..." - referring to Allah SWT)
Bilal bin Rabah RA was whipped at night and with the cuts thus received, was made to lie on the burning ground during the day; and this was done with the aim to make him either forsake Islam or to die a painful death from the wounds. The torturers - namely Abu Jahl, Umayyah and others - would get tired and they would take turns and vie with one another in afflicting more and more painful punishment; but Bilal RA would not yield. Finally Abu Bakr As-Siddiq RA bought his freedom, and he became a free Muslim.
As Islam taught implicitly the oneness of the Almighty Creator, while the idolators of Makkah believed in many gods and goddesses with minor godlings, therefore Bilal RA repeated:
His willingness to suffer as described above shows Bilal RA's love and devotion to Allah. Allah was so dear to him that no amount of persecution could distract him from reciting His Holy name. It is said that the urchins of Makkah would drag him in the streets, with his words "Ahad! Ahad!" ringing in their wake.
Indeed Allah SWT rewarded Bilal bin Rabah RA's steadfastness - even in this world! He was then given the honour to become the Prophet's (SAW) muazzin. Bilal RA was always to remain with Rasulullah SAW at home and abroad to call out the Azaan for the five times obligatory prayers. After the Prophet Muhammad SAW passed away, it became very hard for Bilal RA to continue his stay in Madinah, as he always remembered the Prophet SAW. He therefore left Madinah, and decided to pass the rest of his life striving in the path of Allah. He later became the point of reference for all Muslims in Syria.
Once Bilal RA beheld the Prophet SAW in a dream. The Prophet SAW said to him:
"O, Bilal! How is it that you never visit me."
No sooner did he get up, arranged his travel needs, and then he set out for Madinah.
On reaching there, the grandsons of Rasulullah SAW - Saiyidina Hasan RA and Saiyidina Husain RA requested him to call out the Azaan. Bilal RA could not refuse them, for they were very dear to him.
As soon as the Azaan was called, the people of Madinah started weeping openly out of their anguish - remembering the grand days of the Prophet's (SAW) time. Even the women came out of their houses weeping. Bilal bin Rabah RA left Madinah again after a few days and died in Damascus in 20 A.H.