One theme of the play is the harmful effects that prejudice can have on people. It can make someone want to cut a pound of flesh from a living person. It can make someone spit on the clothing and the beard of an old person. We can sympathize with Shylock because he is the victim of prejudice, but he also is guilty of prejudice. He hates Antonio in part because he is a Christian, although he has some other very good reasons for hating Antonio. We ought not to sympathize with Shylock when he wants Antonio to pay the penalty that is in the contract that Antonio signed.