Merchants circumvented religious prohibitions by buying dispensations to trade with Muslims

Evidence

The Christian and Jewish merchant lords and bankers of Venice, Florence, and Genoa, already implicated by the opportunities, associations, and investments of the previous period, successfully resisted their abhorrences of the Muslim infidel and his nefarious trades. Following the much more frequent practice among clerics of purchasing dispensations to legitimize their bastard offspring, merchants bought dispensations for their commercial trafficking with the infidels. (Pope John XXII (1316–34) may have also used one if he had not had the fortune of being infallible, for he bought forty pieces of gold cloth from Damascus.) Meanwhile, the gold of Africa, the silks, spices, and sugar of the East and Asia Minor were measured by the Italians and their Islamic correspondents against European slaves (Slav, Turkish, Bulgar, and Circassian) and goods. — Cedric J. Robinson, Black Marxism_ The Making of the Black…, 463