" [...] the governor of the Hijaz sent an order to the district governor of Mecca prohibiting the trade in slaves. The district governor was instructed to read the order aloud at the Shari a court of Mecca in the presence of the ulema and the sharifs. This took place on October 30, 1855 [...]

This was the moment for which the sharif had been waiting. On his instructions, Shaykh Jamal issued a fatwa denouncing the ban on the slave trade as contrary to the holy law of Islam. Because of this anti-Islamic act, he said, together with such other anti-Islamic actions as allowing women to initiate divorce proceedings and to move around unveiled, the [Ottomon] Turks had become apostates and heathens. It was lawful to kill them without incurring criminal penalties or bloodwit, and to enslave their children.

"The Turks have become renegades. It is obligatory to make war against them and against those who follow them. Those who are with us are for heaven and those who are with them are for hell. Their blood is lawful and their goods are licit. "

― Bernard Lewis , Race and Slavery in the Middle East: An Historical Enquiry