"The cult of money."
Partly true. I'd say, rather, the cult of preserving one's career in an industry built upon short-lived successes. People are more than one thing usually. DeMille was deeply religious toward the end of his life, and based upon several of his biographies adhered strictly to his Episcopalian upbringing most of his life. Like most of us, however, he failed in this respect on several occasions.

The cult of money.
Which is why he wrapped sensualism in the protective garb of moralism. Pandering to both traditional (and/or hypocritical) Christians and "pagans" was good box office.

Sorry about the lateness of this reply. From a review on Amazon of the book by Simon Louvish:
"He was an Episcopalian and student of the Bible."
I just got my copy today so I've not had a chance to explore further.