People often describe The Merchant of Venice as anti-Semitic for its harsh portrayal of Shylock. But while it does end favorably for the Christians, the play's stance on religion and prejudice is nuanced, and many critics view Merchant as satiric.
Shylock, for example, is not a one-dimensional character—he is emotionally complex (as seen in his "do we not bleed" speech), and he is capable of both love and hate. Shakespeare makes it clear that Shylock's malice is not inherent to him as a Jew. Rather, years of Christian abuse have taught Shylock to be cruel, as evidenced in the line, "The villainy you teach me I will execute."
The Christians, too, are layered. Antonio is incredibly generous to Bassanio, but hateful towards those different from him; Bassanio appears to show Antonio humility, but he may just be manipulative; and Portia, regarded as one of the fairest women in Italy, is heavily prejudiced. Shakespeare's inclusion of the lewd Gratanio also helps to paint the ruling class as less than admirable; he even gets the final line in the play—a sexual pun that, particularly in the wake of Shylock's downfall, leaves the audience mildly uncomfortable.
Ultimately, Merchant is not a play in which the "heroic" characters live up to their best attributes—instead, they seem to always fall to their worst. The play may very well offer a critique of the prejudices that its characters endorse, with a potential goal of getting audiences to consider their own failings.
Act 5, scene 1, opens with Lorenzo musing aloud to Jessica and making some classical allusions:
The moon shines bright. In such a night as this,
When the sweet wind did gently kiss the trees
And they did make no noise, in such a night
Troilus, methinks, mounted the Trojan walls
And sighed his soul toward the Grecian tents / Where Cressid lay that night.
The couple continue to flirt, comparing themselves to other famous lovers of classical legend: Pyramus and Thisbe, Dido and Aeneas, and Medea and Jason. While the moment at first appears idyllic, a closer read proves otherwise, as things end poorly for each of the mentioned mythical couples: Cressida is seduced by another man, a misunderstanding leaves both Pyramus and Thisbe dead, Aeneas abandons Dido to found the city of Rome, and Jason deserts Medea for another woman. This moment with Lorenzo and Jessica therefore alludes to the perils of love, as well as solidifies Merchant as satirical and filled with tensions (e.g., between comedy and tragedy, love and hate, outward appearances and inner truths). Shakespeare intends for his audience to pick up on these allusions, bringing a note of satiric humor to what might first seem like a conventional love scene.