In addition, unlike Othello, whose profession of arms is socially honorable, Shylock is a professional usurer who, like a prostitute, has a social function but is an outcast from the community. But, in the play, he acts unprofessionally; he refuses to charge Antonio interest and insists upon making their legal relation that of debtor and creditor, a relation acknowledged as legal by all societies. Several critics have pointed to analogies between the trial scene and the medieval Processus Belial in which Our Lady defends man against the prosecuting Devil who claims the legal right to man’s soul. […] But the differences between Shylock and Belial are as important as their similarities. The comic Devil of the mystery play can appeal to logic, to the letter of the law, but he cannot appeal to the heart or to the imagination, and Shakespeare allows Shylock to do both. In his "Hath not a Jew eyes…" speech in Act III, Scene I, he is permitted to appeal to the sense of human brotherhood, and in the trial scene, he is allowed to argue, with a sly appeal to the fear a merchant class has of radical social evolution:
You have among you many a purchased slave
Which like your asses and your dogs and mules,
You use in abject and in slavish parts,
which points out that those who preach mercy and brotherhood as universal obligations limit them in practice and are prepared to treat certain classes of human beings as things.
