The Saracens of Tabriz are wicked and treacherous. The law which their prophet Mahomet has given them lays down that any harm they may do to one who does not accept their law, and any appropriation of his goods, is not sin at all. And if they suffer death or injury at the hands of Christians, they are accounted martyrs. For this reason they would be great wrong-doers, if it were not for the government. And all the other Saracens in the world act on the same principle. When they are on the point of death, up comes their priest and asks whether they believe that Mahomet was the true messenger of God; if they answer, ‘Yes’, then he tells them that they are saved. That is why they are converting the Tartars and many other nations to their law, because they are allowed great license to sin and according to their law no sin is forbidden.
Marco Polo: The Travels (1298)