What did Salim, Abu Hudhaifa's freed slave, lead in the Quba mosque, with several companions of the Prophet Muhammad (saw) among them?
 Narrated Ibn `Umar:                     Salim, the freed salve of Abu Hudhaifa used to lead in prayer the early Muhajirin (emigrants) and the companions of the Prophet in the Quba mosque. Among those (who used to pray behind him) were Abu Bakr, `Umar, Abu Salama, and Amir bin Rabi`a.