I was thinking about Belloq today and something occurred to me
in Raiders
Belloq: You and I are very much alike. Archeology is our religion. Yet we have both fallen from the purer faith. Our methods have not differed as much as you pretend. I am a shadowy reflection of you. it would only take a nudge to make you like me, to push you out of the light.
Indy: Now you're getting nasty!
Belloq: You know it's true. How nice. Look at this (holds up a pocket watch) It's worthless. Ten dollars from a vendor in the street. But I take it, I bury it in the sand for a thousand years, it becomes priceless! Like the Ark. Men will kill for it! Men like you and me.
Indy: What about your boss? Der Furher...I thought he was waiting to take possession.
Belloq: All in good time. When I'm finished with it! Jones, do you realize what the Ark is?!? It's a transmitter! A radio for speaking to God!
Now maybe it's just me, but Belloq isn't really thinking this thing through. He's as much as admitted that he's the Bad guy and Indy's the good guy. (albeit a possibly corruptable one in Belloq's estimation) But he wants something that will allow him to communicate with God himself. Not something that will make him God, or even God-like, just a path to an audience with the almighty.
If I were an admitted Bad Guy, i'd be a little more reluctant about going so far out of my way to attract God's attention by using one of his toys in service to the opposition.