Falstaff: If sack and sugar be a fault, God help the wicked. If to be old and merry be a sin, then many an old host that I know is damned. If to be fat be to be hated, then Pharaoh’s lean kine are to be loved. No, my good lord, banish Peto, banish Bardolph, banish Poins, but for sweet Jack Falstaff, kind Jack Falstaff, true Jack Falstaff, valiant Jack Falstaff, and therefore more valiant being, as he is, old Jack Falstaff, banish not him thy Harry’s company, banish not him thy Harry’s company. Banish plump Jack, and banish all the world. 
Prince: I do, I will. 
(Act 2, scene 4, lines 487–98)

This exchange occurs during Harry and Falstaff’s role-playing game meant to help the prince prepare for his upcoming meeting with his father. Falstaff uses his time in the role of King Henry mainly to praise himself, urging Harry to keep Falstaff near him—something that the real king would never do, but which is certainly in keeping with Falstaff’s character. Now, playing Harry, Falstaff lists his own faults, and then excuses each of them: “If sack and sugar be a fault, God help the wicked. If to be old and merry be a sin, then many and old host that I know is damned.” He then goes on to catalog his own supposed virtues, calling himself “sweet,” “kind,” “true,” and “valiant.” Falstaff is not sweet, kind, true, or valiant, but his constant claims to be these things are part of what makes him endearing.

Yet however endearing this speech may be, it’s also ominous. After listing both his faults and his virtues, Falstaff’s speech takes on the tone of a plea. Though he’s still play-acting as the prince speaking to his father, the audience is also aware that, on some level, Falstaff is also speaking for himself and addressing these words to Harry. With this doubleness of address in mind, Falstaff’s plea for Harry—as both play-king and real-prince—not to banish him has an earnest quality. The plea implicitly demonstrates Falstaff’s understanding that he’s an undesirable influence on Harry, and it shows that he worries that Harry will one day renounce him. For his part, Harry’s two-part answer responds from both the perspectives he inhabits. As play-king, he calls for Falstaff to be banished; as real-prince, he proclaims that he will make a similar call in the future. Audiences and readers who are familiar with Henry IV, Part 2 will know that Harry speaks truly, for he will indeed reject Falstaff at the end of the sequel play.