These cowboys and Indians were given away free with Daz in the sixties and my Nana, my dad's mother, used to collect them for me. Cowboys were done in red plastic, Indians in brown. My, I had some fun with them.
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.