Slavery. During the times of Abu Bakr, slavery was a deep rooted institution, and was a conspicuous feature of Makkah. Most of the Quraish were slave owners and thus in the society of Makkah there was a considerable sprinkling of slaves. These slaves were the victims of exploitation, and were treated in an inhuman way by their masters. Many of the slaves were attracted by Islam, for in its teachings lay a charter of freedom for the distressed humanity. Islam preached the cult of equality. It stipulated that all persons were the slaves of God, and no person could be the slave of another person. When many slaves accepted Islam, the slave owners of Makkah felt much concerned, and considered such conversions as a threat to their economic interests.

Persecution of the slaves. Of all the persons who became Muslims, the slaves were the most vulnerable. These men of the Quraish who were converted to Islam continued to enjoy the protection of their respective tribes. The slaves enjoyed no such protection. In order to arrest the progress of Islam among the slaves, the Quraish accordingly resorted to a campaign of persecution and torture against the slaves who professed to be Muslims.

Bilal. Bilal, an Abyssinian who later became the 'Muadhdhin' of Islam was a slave of Umayyah bin Khalaf. Bilal accepted Islam and thereupon his master subjected him to great torture. Umayyah would make Bilal lie down on the burning sand, and would place a huge block of stone on his chest. Umayyah would then ask Bilal to give up Islam, or he would be tortured to death Umayyah would ,sometimes tie a rope round the neck of Bilal, and had him dragged in the streets. Sometimes Bilal was made to put on steel armor, and stand in the hot sun for hours. In spite of these tortures and threats, Bilal remained firm and steadfast in his faith in Islam. The condition of Bilal excited the pity of Abu Bakr. He purchased him from his master and set him free.