Shylock becomes increasingly more bitter and angrier through the events that transpire in Acts I, II, and III. He is bitter and disgusted with the way the Christians treat him, but still use him for borrowing money, and one gets the impression that that has been aggravating him for a long time. But when his daughter, Jessica, elopes with a Christian (Lorenzo) and steals money from him, including a ring that had been a gift from his dead wife, it's like all the bitterness and anger that had been under the surface just explodes. Now he is out for revenge, and what better way than to insist on the pound of flesh owed to him by Antonio for not being able to pay back his debt?
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