G-d interfering

One of the constant refrains often heard from modern theologians is that G-d's existence cannot be proven. Of course, this is consistently refuted in the Tanach. G-d's whole message is that He proves himself by messing with the other guys... Half of the Chumash is setups for G-d to show his might. The Pharaoh's magicians, the test of Korach, Elijah vs the priests of Baal...

On a lighter side, here is some dialog from the "Frisco Kid"

Chief Gray Cloud: Can your God make rain?
Avram: Yes!
Chief Gray Cloud: He doesn’t.
Avram: That’s right.
Chief Gray Cloud: Why?
Avram: Because that's not his department.
Chief Gray Cloud: But if he wanted to he could?
Avram: Yes.
Chief Gray Cloud: What kind of a God do you have?
Avram: Don’t say my God! He’s your God too!
Chief Gray Cloud: Dont give him to us, we’ve got enough trouble with our own gods
Avram: But there’s only one God!
Chief Gray Cloud: What does he do?
Avram: He can do anything!
Chief Gray Cloud: Then why doesn’t he make rain?
Avram: Because he doesn’t make rain.
He gives you strength when you are suffering, He gives us compassion when all that we feel is hatred, He gives us courage when we are searching around blindly like little mice in the darkness , but He does not make rain!

(A sudden flash of lighting, clap of thunder and a sudden cloudburst.)

Avram: Of course, sometimes, just like that, he changes his mind!