In early modern times Malta served as a place of transition between Christendom and the Muslim world. It was a Catholic frontier society under the crusading Knights of St John. The Jews that lived in Malta at the time were few in number and, like the much larger community of Muslims, they were mostly captured slaves. Jews, in particular, were closely watched by the Malta Inquisition Tribunal, which in turn, made great efforts to clarify the boundaries between Christianity, Islam and Judaism particularly because clear parameters made the identification of transgressors easier. A standard feature that emerges from the Inquisition records is the large-scale hostility of Christians against the Jews. As a result Jews were often exposed to unjust charges of corrupting, insulting or otherwise threatening the progress of the Catholic faith. This meant that Jews were often investigated and, at times, prosecuted by the Holy Office.