I crave but this: grace him as he deserves, And let him not be entertained the worse Because he favours me. (Prologue 33-35)
Going a little meta here, but roll with us: there's a lot of prejudice in this play, but the audience is only sensitive to it because, well, there's a lot of prejudice in the real world. Machiavelli's closing words in the Prologue tell the audience that they shouldn't let their own prejudices determine their opinion of Barabas. Also interesting? He doesn't warn them against judging Barabas on the basis of his Judaism, but rather because he "favours" Machiavel.
Enter Barabas in his counting-house, with heaps of gold before him (1.1)
Okay, so this is actually a stage direction, but whatever. If you're watching the play, this is the first thing you see: a Jewish guy, named after a famously bad Jewish guy, indulging in a stereotypically Jewish pastime (counting his money, of which he has a lot). Before Barabas ever says a single word, you're set up to understand that he's going to be characterized largely as a stock Jewish character; he's already the anti-Semitic Big Bad.
BARABAS: Are strangers with your tribute to be taxed?
SECOND KNIGHT: Have strangers leave with us to get their wealth? Then let them with us contribute.
BARABAS: How, equally?
FERNEZE: No, Jew, like infidels. For through our suff'rance of your hateful lives, Who stand accursed in the sight of heaven, These taxes and afflictions are befall'n (1.2.62-5)
Barabas wants to know why all the Maltese Christians aren't contributing to the tribute money, at which point Ferneze pulls the Not Really Citizens Card.The Jews, who are "accursèd in the sight of heaven," aren't allowed to be proper citizens, so obviously they can be subjected to special (and in this case really arbitrary and unfair) treatment. Way harsh, Tai.
If your first curse fall heavy on thy head And make thee poor and scorned of all the world, 'Tis not our fault but thy inherent sin. (1.2.107-9)
Here, Ferneze claims that confiscating the Jews' property is really just the proper order of things. Why? Because Christians think Jews have "inherent sin" because they basically voted for the crucifixion of Christ way back when. That's right: Ferneze is telling the Jews that he's taking all their stuff because it's his religious duty to punish them for something the Jews did 1500 years ago. What a nice guy, right?
BARABAS: Good sir, your father has deserved it at my hands, Who, of mere charity and Christian ruth, To bring me to religious purity And, as it were, in catechizing sort, To make me mindful of my mortal sins, Against my will, and whether I would or no, Seized all I had, and thrust me out of doors, And made my house a place for nuns most chaste.
LODOWICK: No doubt your soul shall reap the fruit of it. (2.3.70-77)
Sure, we could have easily put this in the Themes: Hypocrisy section, but it works here, too: Ferneze can get only away with hypocrisy because of the prejudices against Jews. Here, Barabas is laying out the super obvious wrongs that Ferneze has done him, but Lodowick thinks it's fine. Why? Because, Barabas is telling the story of "a powerful man took advantage of me and stole everything I had," but Lodowick is hearing the story of "a good Christian man corrected, as was his religious duty, a sinful Jew."
But I perceive there is no love on earth, Pity in Jews, nor piety in Turks. (3.3.47-8)
Abigail, having learned of her father's hand in Mathias and Lodowick's deaths, basically decides that all of these groups are equally contemptible (including her own religious community) and becomes a nun. Girl, we hear you. This place kind of drools. That said, it's debatable whether joining a nunnery in Marlowe's world actually gets you to a better place.
But now experience, purchased with grief, Has made me see the difference of things. (3.3.61-62)
Abigail is one of the few characters who doesn't make a lot of bigoted remarks. Here, though, when she's committing to really become a nun, she says she's become sensitive to the "difference of things," a signal that even she is becoming prejudiced. But is this really prejudice? Maybe not. She sees the difference through "experience"—the exact opposite of pre-judice.
Ithamore: 'Tis a strange thing of that Jew: he lives upon pickled grasshoppers and sauced mushrumbs.
Barabas: [Aside]: What a slave's this? The Governor feeds not as I do.
Ithamore: He never put on a clean shirt since he was circumcised.
Barabas: [Aside]: Oh, rascal! I change myself twice a day.
Ithamore: The hat he wears, Judas left under the elder when he hanged himself.
Barabas: [Aside] 'Twas sent me for a present from the Great Cham. (4.4. 60-67)
Ithamore was all about being Barabas's "fellow" when he was a disempowered, newly bought slave. But now that he's sitting pretty with Bellamira and her pimp, he gets to be to be as prejudiced as everybody else. Also, was anybody else amused that Barabas has a hat given to him by a Chinese Emperor who's been dead for 300 years or so?
To undo a Jew is a charity and not a sin. (4.4.79)
Ithamore is echoing Barabas's earlier declaration to Abigail that "It's no sin to deceive a Christian" (2.3.309-12). The Christians and the Jews both appear to believe that you only have to be nice to people in your own religious communities. Nice people, right?