Who says the painter of the eggshell ever listened to talks about god or that music? Since he's famous because of irony I assume he want to show something or better make something clear.How about hypocrism of those who claim to believe and point fingers at others and change the rules to make them fit for them?
Can it be that religion back then was mainly meant to keep the people dumb and fear for their lives while a very small group lived in luxury drinking wine and eating like pigs while singing Halleluja, praise the lord, blah, blah, blah while they in the meanwhile commit every sin?

Coulourful picture you shared.