[Alfie helpfully points out the meanings, even if he doesn't ask, and after the waiter has taken their orders (Alfie just gets a plain slice of cheese for himself), he leans forward with his elbow on the table, clasping his hands in front of him.]

Right. I'll be needing someone to take a box and an envelope across town this afternoon - delivery before five. The envelope, that's gonna have money in it, and both myself and the recipient will know exactly how much is supposed to be in it.

[The implication being: if you skim off the top, you will get caught.]