 In the Spanish preface, Fra Marino records his wish that the Gospel of Barnabas should be printed, and the only place in Europe where that would have been possible in the late 16th century would have been Istanbul.The lost Spanish manuscript claimed to have been written in Istanbul, and the surviving Italian manuscript has several Turkish features; so, whether the language of origin was Spanish or Italian, Istanbul is regarded by most researchers as the place of origin of the two known texts.A minority of researchers – such as David Sox – are, however, suspicious of the apparent 'Turkish' features of the Italian manuscript; especially the Arabic annotations, which they adjudge to be so riddled with elementary errors as to be most unlikely to have been written in Istanbul (even by an Italian scribe).