I took opportunity while I was away to do some reading, of course. I wanted to read Steinbeck's Of men and mice because kids read it in school these days and I was curious. So I now know why it has the title it has (not just the Burns reference) and I'm familiar with the basic story. It's a good story, well written but as it is only a novella it works at a fairly superficial level - great for kids starting on serious literature. I've never seen any of the movie versions. I started The grapes of wrath once may be I'll have another go.
Bonhoeffer uses a similar phrase 'worldly Christianity'. It's J Gresham Machen that I want to line up most closely with. See his Christianity and culture here. Having done commentaries on Proverbs (Heavenly Wisdom) and Song of Songs (Heavenly Love), a matching title for Ecclesiastes would be Heavenly Worldliness. For my stance on worldliness, see 3 posts here.