Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) narrates: A slave pledged allegiance for migration at the blessed hand of the Prophet (peace and blessings be upon him). Then his owner, searching for him, came to the service of the Prophet (peace and blessings be upon him). The narrator states: The Prophet (peace and blessings be upon him) bought that slave in exchange for two black slaves. After that, the Prophet (peace and blessings be upon him) did not accept the pledge of allegiance from anyone until he first inquired whether he was a slave.