We had our last session on Unseen Realities last night. Eleven of us gathered and we looked again at Satan and the fact he is bound. I think people were happy with the line I took, beginning with Matthew 12:29. We had a full prayer time with mostpeople praying before the close. Four of us present are preaching in various places on the coming Lord's Day.
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.