For Harpagon, money equals life, and every dollar he loses is like a drop of blood leaving his body. Whenever you see the guy spend the smallest amount money, you just cringe at the amount of suffering he feels. And with Harpagon, it's always tough to know when he's exaggerating and when he's being literal when it comes to money.
When he discovers that his cash box has been stolen, Harpagon totally loses his mind, shouting out, "They've cut my throat! They've stolen my money!" (4.7.1). For Harpagon, these two statements mean the exact same thing: to steal his money is the same thing as cutting his throat. He continues in this vein by saying, "It's the end, I can't go on, I'm as good as dead and buried" (4.7.1).
We might feel a little sympathy for Harpagon when he turns to us and asks "Won't somebody bring me back to life […][?]" Here, it sounds like he's asking whether anyone will care if he's alive or dead. But when he finishes the sentence by saying, "by returning my money" (4.7.1), we realize that all he's actually asking whether he'll get his money back.
Harpagon's rant is made more ludicrous by the fact that this play is littered with near-death experiences. Élise almost drowns, and is saved by Valère. Anselme thinks that his entire family has been dead and gone for almost twenty years. There's a serious presence of death in this play, even though everything is sunny and very much full of life by the play's conclusion. The presence of real death makes Harpagon's comparison of losing his money to losing his life all the more bombastic, and all the more pathetic.