Got to thinking about Bazooka Joe bubble gum today. For one old penny you could buy a piece of pink gum (very hard at first) wrapped in wax paper with a small comic strip inside. As ever the internet is brilliant. See here if you remember it too - or if you don't.
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.