I always heard this "nothing to hide, nothing to fear" attitude/saying attributed to goebbels and went to go find the source.

I fell down the research well and found it's actually from an author I've read but evidently not enough of his work: Upton Sinclair.

The source is The Profits of Religion and "Sinclair attacks institutionalized religion as a 'source of income to parasites, and the natural ally of every form of oppression and exploitation.'"

Seems sadly relevant to today.