throughout the book, Shylock is portrayed as rather inhumane, with little pity and emotion. he demanded a pound of flesh from Antonio, and seemed totally void of pity when begged for mercy. also, when his daughter left home, he hoped not for his dauhgter, but the small fortune that the daughter had gone off with.
with these two forms of description, Shylock seems like a riches above kin, revenge over humane kind of person, and the further emphasis on the fact that he is a Jew makes people all the more strereotypical towards the jews
also, in the court scene, he is portrayed as some one who would rather accept punishment than repent, which goes to show how much Shylock is devoted to his religion, which was then not a very highly-respected religion.
Also, he was portrayed as the type of person who was bullied by the christians. through verbal insults and acts like spitting, there was an obvious hatred Shylock had towards the Christians, which are a sort of evidence ans wering the question of Shylocks prejudice.
thus, this puts Shylock in a better, and worse light. Now, he is someone who is not just snapping at the Christians randomly, but has his own reasons for doing so. also, he is put into an even worse light than before because he now seems like a lunatic bent on revenge.
thus, i am guessing that this was probably shakespeares point of view of the Jews at that time.
he was probably trying his best to condense the general Jew under a single character, whether to ridicule or help them