He has had a dream that there will be trouble tonight, and there actually is Launcelot slyly jokes that Shylock will in fact see a "masque" that night. Shylock brushes him off and repeats that Jessica should lock the doors and not look out onto the street. In an aside, Launcelot says that Jessica should look out the window—a Christian will come by who will be worth a Jew's eye. Launcelot, who is in on Jessica and Lorenzo's scheme to elope, can make jokes with her that her father is unable to understand. As Christians (or, in Jessica's case, soon-to-be Christians), they're insiders while the Jewish Shylock is an outsider.